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Recent Canonical Ubuntu Linux Security Advisories

Advisory Title Published
USN-8426-1 USN-8426-1: Linux kernel (Azure) vulnerabilities June 11, 2026
USN-8423-1 USN-8423-1: lwIP vulnerabilities June 11, 2026
USN-8424-1 USN-8424-1: Ubuntu Kylin Software Center vulnerability June 11, 2026
USN-8422-1 USN-8422-1: Mistral vulnerability June 11, 2026
USN-8421-1 USN-8421-1: Ironic vulnerabilities June 11, 2026
USN-8420-1 USN-8420-1: .NET vulnerabilities June 11, 2026
USN-8419-1 USN-8419-1: HTTP-Daemon vulnerability June 10, 2026
USN-6455-2 USN-6455-2: Exim regression June 10, 2026
USN-8130-3 USN-8130-3: GStreamer Base Plugins vulnerability June 10, 2026
USN-8418-1 USN-8418-1: Crypt-SaltedHash vulnerability June 10, 2026

By the Year

In 2026 there have been 826 vulnerabilities in Canonical Ubuntu Linux with an average score of 6.5 out of ten. Last year, in 2025 Ubuntu Linux had 2883 security vulnerabilities published. Right now, Ubuntu Linux is on track to have less security vulnerabilities in 2026 than it did last year. However, the average CVE base score of the vulnerabilities in 2026 is greater by 0.17.




Year Vulnerabilities Average Score
2026 826 6.51
2025 2883 6.33
2024 3573 6.40
2023 1079 6.88
2022 1210 6.99
2021 750 6.87
2020 753 6.23
2019 793 6.98
2018 929 7.10

It may take a day or so for new Ubuntu Linux vulnerabilities to show up in the stats or in the list of recent security vulnerabilities. Additionally vulnerabilities may be tagged under a different product or component name.

Recent Canonical Ubuntu Linux Security Vulnerabilities

Jun 2026: ASP.NET Core Denial of Service Vulnerability
CVE-2026-45591 7.5 - High - June 09, 2026

Uncontrolled resource consumption in ASP.NET Core allows an unauthorized attacker to deny service over a network.

Resource Exhaustion

Jun 2026: .NET Tampering Vulnerability
CVE-2026-45491 6.2 - Medium - June 09, 2026

Improper link resolution before file access ('link following') in .NET allows an unauthorized attacker to perform tampering locally.

insecure temporary file

OpenSSL PKCS#7 UAF via PKCS7_verify(); FIPS 3.6+ safe
CVE-2026-45447 8.8 - High - June 09, 2026

Issue summary: A specially crafted PKCS#7 or S/MIME signed message could trigger a use-after-free during PKCS#7 signature verification. Impact summary: A use-after-free may result in process crashes, heap corruption, or potentially remote code execution. When processing a PKCS#7 or S/MIME signed message, if the SignedData digestAlgorithms field is present as an empty ASN.1 SET, OpenSSL may incorrectly free a caller-owned BIO during PKCS7_verify(). A subsequent use of the BIO by the calling application results in a use-after-free condition. In the common case this occurs when the application later calls BIO_free() on the BIO originally passed to PKCS7_verify(). Depending on allocator behavior and application-specific BIO usage patterns, this may result in a crash or other memory corruption. In some application contexts this may potentially be exploitable for remote code execution. Applications that process PKCS#7 or S/MIME signed messages using OpenSSL PKCS#7 APIs may be affected. Applications using the CMS APIs for this processing are not affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

Dangling pointer

OpenSSL EVP Provider: AESSIV/AESGCMSIV Auth Forger via Empty AAD/Ciphertext (<3.2)
CVE-2026-45446 4.8 - Medium - June 09, 2026

Issue summary: The implementations of AES-SIV (RFC 5297) and AES-GCM-SIV (RFC 8452) mishandle the authentication of AAD (Additional Authenticated Data) with an empty ciphertext allowing a forgery of such messages. Impact summary: An attacker can forge empty messages with arbitrary AAD to the victim's application using these ciphers. AES-SIV (RFC 5297) and AES-GCM-SIV (RFC 8452) are nonce-misuse-resistant AEAD modes: they accept a key, nonce, optional AAD (bytes that are authenticated but not encrypted), and plaintext, and produces ciphertext plus a 16-byte tag. On decrypt, `EVP_DecryptFinal_ex()` is documented to return success only if the tag is verified succesfully. In OpenSSL's provider implementation of these ciphers, the expected tag is computed only when decryption function is invoked with non-empty data. If the caller supplies AAD and then calls `EVP_DecryptFinal_ex()` without invocation of the ciphertext update, which can happen when the received ciphertext length is zero, the tag is never recalculated and still holds its all-zeros value. When AES-GCM-SIV is used, an attacker who sends arbitrary AAD, empty ciphertext, and all-zeros tag passes authentication under any key they do not know, single-shot. When AES-SIV is used, for mounting the attack it's necessary for the application to reuse the decryption context without resetting the key. AES-SIV is implemented since OpenSSL 3.0. AES-GCM-SIV is implemented since OpenSSL 3.2. No protocols implemented in OpenSSL itself (TLS/CMS/PKCS7/HPKE/QUIC) support either AES-GCM-SIV or AES-SIV. To mount an attack, the applications must implement their own protocol and use the EVP interface. Also they must skip the ciphertext update when a message with an empty ciphertext arrives. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as these algorithms are not FIPS approved and the affected code is outside the OpenSSL FIPS module boundary.

Missing Cryptographic Step

OpenSSL EVP_Cipher One-Shot API Discards IV causing AES-OCB nonce reuse
CVE-2026-45445 7.5 - High - June 09, 2026

Issue summary: When an application drives an AES-OCB context through the public EVP_Cipher() one-shot interface, the application-supplied initialisation vector (IV) is silently discarded. Impact summary: Every message encrypted under the same key uses the same effective nonce regardless of the IV supplied by the caller, resulting in (key, nonce) reuse and loss of confidentiality. If the same code path is used to compute the authentication tag, the tag depends only on the (key, IV) pair and not on the plaintext or ciphertext, allowing universal forgery of arbitrary ciphertext from a single captured message. OpenSSL provides two ways to drive a cipher: the documented streaming interface (EVP_CipherUpdate / EVP_CipherFinal_ex) and a lower-level one-shot, EVP_Cipher(), whose documentation explicitly recommends against use by applications in favour of EVP_CipherUpdate() and EVP_CipherFinal_ex(). The OCB provider's streaming handler flushes the application-supplied IV into the OCB context before processing data; the one-shot handler did not. Every call to EVP_Cipher() on an AES-OCB context therefore ran with the all-zero key-derived offset state left by cipher initialisation, regardless of the caller's IV. If EVP_EncryptFinal_ex() is subsequently used to obtain the authentication tag, the deferred IV setup runs at that point and clears the running checksum that should have been accumulated over the plaintext. The resulting tag is a function of (key, IV) only and verifies against any ciphertext produced under the same (key, IV) pair. The OpenSSL SSL/TLS implementation is not affected: AES-OCB is not a TLS cipher suite, and libssl does not call EVP_Cipher() in any case. Applications that drive AES-OCB through the documented streaming AEAD API (EVP_CipherUpdate / EVP_CipherFinal_ex) are not affected. Only applications that combine the AES-OCB cipher with the EVP_Cipher() one-shot API are vulnerable. The FIPS modules in 4.0, 3.6, 3.5, 3.4 and 3.0 are not affected by this issue, as AES-OCB is outside the OpenSSL FIPS module boundary.

Missing Cryptographic Step

OpenSSL FIPS 3.0-4.0 DHX X9.42 subgroup check flaw
CVE-2026-42770 3.7 - Low - June 09, 2026

Issue summary: When EVP_PKEY_derive_set_peer() is called with a DHX (X9.42) peer key, the peer key is not properly checked for the subgroup membership. Impact summary: A malicious peer which presents an X9.42 key carrying the victim's p and g parameters, a forged q = r (a small prime factor of the cofactor (p1)/q_local), and a public value Y of order r can recover the victim's private key after a small number of key exchange attempts. When EVP_PKEY_derive_set_peer() is called with a DHX (X9.42) peer key, the subgroup membership check Y^q 1 (mod p) is performed using the peer's own q parameter, not the local key's q. The peer's domain parameters are then matched against the domain parameters of the private key, but the value of q is not compared. A malicious peer who presents an X9.42 key carrying the victim's p, g, a forged q = r (a small prime factor of the cofactor), and a public value Y of order r passes all checks. The shared secret then takes only r distinct values, leaking priv mod r. Repeating for each small-prime factor of the cofactor and combining via CRT recovers the full private key (LimLee / small-subgroup-confinement attack). The realistic attack surface is narrow: principally CMP deployments with long-lived RA/CA DHX keys and bespoke enterprise or government applications using X9.42 DHX static keys with interactive protocols and therefore this issue was assigned Low severity. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are affected by this issue.

Missing Cryptographic Step

OpenSSL CMP Root CA Key Update Validation Bypass RA Cred Escalation
CVE-2026-42769 5.3 - Medium - June 09, 2026

Issue Summary: An error in the callback used to verify the certificate provided in a Root CA key update Certificate Management Protocol (CMP) message response rendered the certificate validation ineffectual, which could lead to escalation of credentials from the Registration Authority (RA) level to the root Certification Authority (root CA) level. Impact Summary: The Registration Autority could replace the root CA certificate for the CMP clients with an arbitrary root CA certificate. One of the parts of the Certificate Management Protocol (CMP), specified in RFC 9810, is Root Certification Authority (root CA) key Rollover, which is sent by the server in a message with type 'id-it-rootCaKeyUpdate'. As part of these messages, 'newWithOld' certificate, the new root CA certificate signed with the old root CA key, is provided, and verifying its signature is crucial for transferring the trust from the old CA key to the new one. The 'id-it-rootCaKeyUpdate' messages are expected to be processed with OSSL_CMP_get1_rootCaKeyUpdate(), that is expected to verify the 'newWithOld' certificate. A typo in the certificate chain building code led to adding an incorrect certificate ('newWithOld' instead of 'oldRoot') to the certificate chain, rendering the certificate verification process ineffectual (only the issuer name and the algorithm OIDs were verified by other parts of the verification code). An attacker who already has credentials that satisfy the CMP message protection checks can generate a new key pair and use a crafted self-signed certificate in its 'id-it-rootCaKeyUpdate' CMP messages which affected CMP clients would accept as a new trust anchor. Significant preconditions for the attack (having valid RA-level credentials) are the reason the issue was assigned Low severity. The FIPS modules are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

Improper Certificate Validation

OpenSSL <3.2 CMS PKCS7 Bleichenbacher Oracle
CVE-2026-42768 3.7 - Low - June 09, 2026

Issue summary: The CMS_decrypt and PKCS7_decrypt functions are vulnerable to Bleichenbacher-style attack when an attacker is able to provide the CMS or S/MIME messages and observe the error code and/or decryption output. Impact summary: The Bleichenbacher-style attack allows an attacker to use the victim's vulnerable application as a way to decrypt or sign messages with the victim's private RSA key. The attack is possible in 2 variants. 1. The decryption API (CMS_decrypt(), PKCS7_decrypt()) is used without providing the recipient certificate. In this case OpenSSL iterates over every KeyTransRecipientInfo (KTRI) without stopping at the first success. An attacker who authors a message with two KTRI entries the first one wrapping a real CEK under the victim's public key, the second with an arbitrary probe ciphertext obtains opportunity to iterate the 2nd KTRI to get a valid PKCS#1 v1.5 padding if the error code of the application is available. That is a Bleichenbacher oracle (Bleichenbacher, CRYPTO '98): an adaptive-chosen-ciphertext side channel from which the attacker decrypts any RSA ciphertext to the victim's key or forges any PKCS#1 v1.5 signature under it. 2. When the decryption API (CMS_decrypt(), PKCS7_decrypt()) is provided with the recipient certificate, and the recipient is not found, a random key is substituted. An attacker who authors a message and is able to compare both error code and the result of the decryption, can mount a Bleichenbacher oracle. We are not aware of any applications that provide a remote attacker an opportunity to mount an attack described in these scenarios. We consider the existence of such application very unlikely, and for this reason this CVE has been evaluated as Low severity. To avoid these attacks, when RSA PKCS#1 v1.5 Key Transport is in use, the invoked EVP_PKEY_decrypt() will use the implicit rejection mechanism described in draft-irtf-cfrg-rsa-guidance. In previous OpenSSL releases the implicit rejection was explicitly disabled. The implicit rejection mechanism always returns a plaintext value, the symmetric key. This result is deterministic for the ciphertext and the private key. The length of the decryption result can happen to match the length of the key of the symmetric cipher that was used for the content encryption. When a certificate is not provided, the last RecipientInfo producing a key that looks valid will be used. It may cause getting garbage content on decryption. As a proper way to deal with this a recipient certificate has to be provided to identify the particular RecipientInfo for decryption. The FIPS modules in 4.0, 3.6, 3.5, and 3.4 are not affected by this issue, as CMS and S/MIME processing happens outside the OpenSSL FIPS module boundary.

Covert Channel

OpenSSL CMP Client Null Deref DoS (pre-3.5) via crafted EncryptedValue OID
CVE-2026-42767 5.9 - Medium - June 09, 2026

Issue summary: An attacker-controlled CMP (Certificate Management Protocol) server could trigger a NULL pointer dereference in a CMP client application. Impact summary: A NULL pointer dereference causes a crash of the application and a Denial of Service. An attacker controlling a CMP server (or acting as a man-in-the-middle) could craft a CMP response containing a CRMF (Certificate Request Message Format) CertRepMessage with an EncryptedValue structure where the symmAlg field has an algorithm OID but no parameters field. When the OpenSSL CMP client processes this response, the NULL dereference occurs, causing a crash of the CMP client. Applications that process untrusted CMP/CRMF messages may be affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

NULL Pointer Dereference

OpenSSL CMS NULL Deref (before 4.0) - DoS
CVE-2026-42766 5.9 - Medium - June 09, 2026

Issue summary: A specially crafted password-encrypted CMS message can trigger a NULL pointer dereference during CMS decryption. Impact summary: This NULL pointer dereference leads to an application crash and a Denial of Service. The CMS PasswordRecipientInfo.keyDerivationAlgorithm field is defined as OPTIONAL in the ASN.1 specification and may therefore be absent in specially crafted inputs. During the password-based CMS decryption the OpenSSL CMS implementation dereferences this field without first checking whether it was present. An attacker who supplies such a CMS message to an application performing password-based CMS decryption can trigger an application crash, leading to a Denial of Service. Applications that process password-encrypted CMS messages may be affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

NULL Pointer Dereference

OpenSSL QUIC Server NULL ptr deref (addr val disabled)
CVE-2026-42764 7.5 - High - June 09, 2026

Issue summary: Receiving a QUIC initial packet with an invalid token may trigger a NULL pointer dereference in the OpenSSL QUIC server with address validation disabled. Impact summary: NULL pointer dereference typically causes abnormal termination of the affected QUIC server process and a Denial of Service. If the address validation is disabled in the OpenSSL QUIC server implementation, an attacker can crash the server by sending an initial packet with an invalid or expired token. By default, the client address validation is enabled in the OpenSSL QUIC server implementation, which makes the default configuration not vulnerable to this issue. However if the SSL_LISTENER_FLAG_NO_VALIDATE is used with the SSL_new_listener() call, the address validation is disabled making the vulnerable code reachable. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

NULL Pointer Dereference

OpenSSL QUIC Heap Exhaustion via PATH_CHALLENGE Flood (before 4.0)
CVE-2026-34183 7.5 - High - June 09, 2026

Issue summary: Remote peer may exhaust heap memory of the QUIC server or client by flooding it with packets containing PATH_CHALLENGE frames. Impact summary: A malicious remote peer can cause an unbounded memory allocation which can lead to an abnormal termination of the application acting as a QUIC client or server and a Denial of Service. A remote peer may exhaust heap memory by flooding the local QUIC stack with PATH_CHALLENGE frames. The local QUIC stack allocates a PATH_RESPONSE frame for every PATH_CHALLENGE it receives. The allocated PATH_RESPONSE frame gets freed only when the remote peer acknowledges reception of the PATH_RESPONSE frame which will not be done by a malicious peer. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue. The QUIC stack is outside of OpenSSL FIPS module boundary.

Stack Exhaustion

OpenSSL CMS AuthEnvelopedData Cipher/Tag Length Validation Flaw
CVE-2026-34182 9.1 - Critical - June 09, 2026

Issue Summary: Cryptographic Message Services (CMS) processing fails to perform sufficient input validation on the cipher and tag length fields of AuthEnvelopedData containers, leading to various potential compromises. Impact Summary: Attackers making use of these vulnerabilities may achieve key-equivalent functionality for a given CMS recipient and/or bypass integrity validation for a given message. In one use case, an attacker may send a CMS message containing AuthEnvelopedData with the cipher specified as a non-AEAD cipher. OpenSSL erroneously allows this selection, and attempts to decrypt and validate the message. An on-path attacker who captures one legitimate AES-GCM AuthEnvelopedData addressed to the victim can re-emit it with the recipientInfos set left byte-for-byte intact, so the victim's private key still unwraps the genuine CEK (the content-encryption key), but with the inner OID rewritten to AES-256-OFB (Output Feedback Mode, an unauthenticated keystream mode) and with an attacker-chosen IV and ciphertext. The victim initializes AES-256-OFB under the real CEK, never consults the MAC field, and CMS_decrypt() returns success. If the application under attack responds to the attacker with any indicator showing success or failure of the decryption effort, it is possible for the attacker to use this as an oracle to obtain key equivalent functionality for the CEK used for the chosen recipient of the message. In another use case, an attacker can reduce the tag length of the chosen AEAD cipher for a given AuthEnvelopedData container to be a single byte long, allowing an attacker to brute force CMS decryption, producing an integrity bypass for applications that trust CMS_decrypt() to reject modified content. The FIPS modules are not affected by this issue.

Improper Validation of Integrity Check Value

OpenSSL PKCS#12 PBMAC1 forging CVE-2026-34181
CVE-2026-34181 7.4 - High - June 09, 2026

Issue Summary: The PKCS#12 file processing fails to perform sufficient input validation for files that use Password-Based Message Authentication Code 1 (PBMAC1) integrity mechanism allowing a certificate and private key forgery. Impact Summary: An attacker impersonating a user can cause a service reading PKCS#12 files to accept forged certificates and private keys with a 1 in 256 probability. If a service accepting PKCS#12 files is using passwords for authenticating the received files, the attacker can create unencrypted PKCS#12 files that use PBMAC1 authentication that specifies an HMAC key of only one byte, allowing them to craft a file that will be accepted with a 1 in 256 probability. That would then cause the service to accept a certificate and private key controlled by the attacker. The FIPS modules are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

Improper Validation of Integrity Check Value

OpenSSL ASN.1 Decoder Heap Buffer Over-Read (1.1.1+) on 64-bit Unix
CVE-2026-34180 7.5 - High - June 09, 2026

Issue summary: Parsing a crafted DER-encoded ASN.1 structure with a primitive element whose content exceeds 2 gigabytes in length may cause a heap buffer over-read on 64-bit Unix and Unix-like platforms. Impact summary: The heap buffer over-read may crash the application (Denial of Service) or to load into the decoded ASN.1 object contents of memory beyond the end of the input buffer. More typically such ASN.1 elements would instead be truncated. An integer truncation in OpenSSL's ASN.1 decoder causes the content length of an ASN.1 primitive element to be mishandled when it exceeds 2 gigabytes. In the worst case the truncated length is treated as a request to scan the binary content for a terminating zero byte, possibly causing OpenSSL to read either less than or beyond the end of the allocated buffer. Applications that pass attacker-supplied data to d2i_X509(), d2i_PKCS7(), or any other d2i_* decoding function are affected. OpenSSL's own command-line tools are not vulnerable, as data read through the BIO layer is checked before it reaches the affected code. The issue only affects 64-bit Unix and Unix-like platforms; 32-bit platforms and 64-bit Windows are not affected. The FIPS modules in 4.0, 3.6, 3.5, 3.4 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

Out-of-bounds Read

OPENSSL CMS Heap OOB Read via Stream-Mode KEK in CMS Decrypt
CVE-2026-9076 7.5 - High - June 09, 2026

Issue summary: When CMS password-based decryption (RFC 3211 / PWRI key unwrap) processes attacker-supplied CMS data, an attacker-chosen stream-mode KEK cipher can trigger a heap out-of-bounds read in kek_unwrap_key(). Impact summary: A heap buffer over-read may trigger a crash which leads to Denial of Service for an application if the input buffer ends at a memory page boundary and the following page is unmapped. There is no information disclosure as the over-read bytes are not revealed to the attacker. The key unwrapping function performs a check-byte test as specified in the RFC that reads 7 bytes from a heap allocation that is based on the wrapped key length from the message. There is a minimum length check based on the block length of the wrapping cipher. However the cipher is selected from an OID carried in the attacker's PWRI keyEncryptionAlgorithm with no requirement that the cipher be a block cipher. When an attacker selects a stream-mode cipher the guard will be ineffective and the allocated buffer containing the unwrapped key can be too small to fit the check-bytes specified in the RFC and a buffer over-read can happen. Applications calling CMS_decrypt() or CMS_decrypt_set1_password() (equivalently openssl cms -decrypt -pwri_password ...) on untrusted CMS data are vulnerable to this issue. No password knowledge is required: the over-read happens during the unwrap attempt before any authentication succeeds. The over-read is limited to a few bytes and is not written to output, so there is no information disclosure. Triggering a crash requires the allocation to border unmapped memory, which is unlikely with the normal allocator. The FIPS modules are not affected by this issue.

Out-of-bounds Read

OpenSSL <=3.1: Signed Int Overflow in ASN1_mbstring_ncopy() Heap BOV
CVE-2026-7383 8.1 - High - June 09, 2026

Issue summary: A signed integer overflow when sizing the destination buffer for Unicode output in ASN1_mbstring_ncopy() can lead to a heap buffer overflow. Impact summary: A heap buffer overflow may lead to a crash or possibly attacker controlled code execution or other undefined behaviour. In ASN1_mbstring_copy() and ASN1_mbstring_ncopy() the destination size for Unicode output is computed in a signed int: by left shift of the input character count for BMPSTRING (UTF-16) and UNIVERSALSTRING (UTF-32), and by summing per-character byte counts for UTF8STRING. The calculation overflows when the input reaches around 2^30 characters. In the worst case (UNIVERSALSTRING at 2^30 characters) the size wraps to zero, OPENSSL_malloc(1) is called, and the subsequent character copy writes several gigabytes past the one-byte allocation. X.509 certificate processing routes through ASN1_STRING_set_by_NID(), whose DIRSTRING_TYPE mask excludes UNIVERSALSTRING and whose per-NID size limits cap the input length; no network protocol or certificate-handling path in OpenSSL exercises the overflow. Triggering the bug requires an application that calls ASN1_mbstring_copy() or ASN1_mbstring_ncopy() directly, or registers a custom string type via ASN1_STRING_TABLE_add(), with attacker-controlled input on the order of half a gigabyte or more. For these reasons this issue was assigned Low severity. The FIPS modules in 4.0, 3.6, 3.5, 3.4 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

Memory Corruption

OpenVPN 2.6.0-2.6.19/2.7_alpha1-2.7.1 UAF via TLS session promotion
CVE-2026-40215 - June 08, 2026

A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.

Out-of-bounds Read

OpenVPN 2.6.x-2.7.1 TLS-Crypt-V2 Length Validation DoS
CVE-2026-35058 - June 08, 2026

Improper validation of packet length during tls-crypt-v2 key extraction in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows authenticated attackers to trigger a fatal assertion and cause a denial of service via a specially crafted packet.

assertion failure

Apache HTTP Server mod_http DoS via Excessive Memory Allocation (2.4.17-2.4.67)
CVE-2026-49975 7.5 - High - June 08, 2026

Memory Allocation with Excessive Size Value vulnerability in Apache HTTP Server's mod_http leads to denial of service via malicious HTTP requests. This issue affects Apache HTTP Server: from 2.4.17 through 2.4.67.

Stack Exhaustion

Samba WINS NULL Deref via UDP (CVE-2026-3238)
CVE-2026-3238 7.5 - High - June 08, 2026

A flaw was found in Sambas WINS server component when running as an Active Directory Domain Controller. The WINS protocol handlers for certain request types did not properly validate incoming packets, allowing an unauthenticated remote attacker to trigger a NULL pointer dereference and crash the WINS service using specially crafted UDP packets.

NULL Pointer Dereference

OpenStack Ironic <35.0.2 Local File Read via PXE Template
CVE-2026-44917 4.9 - Medium - June 04, 2026

OpenStack Ironic before 35.0.2 allows a malicious authenticated project admin or manager to read local files on the Ironic conductor via a pxe_template.

Incorrect Resource Transfer Between Spheres

OpenStack Ironic <35.0.2: DT File Overwrite Vulnerability in ISO Deployer
CVE-2026-48681 5.9 - Medium - June 04, 2026

OpenStack Ironic through before 35.0.2 allows file overwrite via directory traversal during deployment with a crafted ISO image.

Relative Path Traversal

OpenStack Ironic <=35.0.x Boot Script Injection
CVE-2026-46447 5.8 - Medium - June 03, 2026

OpenStack Ironic before 35.0.2 allows Boot Script Injection of an iPXE script if the attacker can set node.driver_info or node.instance_info.

Incorrect Resource Transfer Between Spheres

GnuTLS PKCS#7 Padding Timing SideChannel Info Disclosure
CVE-2026-5419 3.7 - Low - June 01, 2026

A flaw was found in gnutls. The PKCS#7 padding check, performed during decryption, was not constant-time. This timing side-channel could allow a remote attacker to potentially leak sensitive information about the padding bytes through observable timing differences. This vulnerability is a form of information disclosure.

Observable Timing Discrepancy

Null Deref in AF_INET/AF_INET6 Oops on Ubuntu Kernel 6.8/6.17/7.0
CVE-2026-47337 3.3 - Low - May 28, 2026

Ubuntu Linux 6.8, 6.17 and 7.0 contain SAUCE patches with a possible NULL pointer dereference in the handling of AF_INET/AF_INET6 socket mediation. The bug can be triggered by an unprivileged local user. This can lead to a kernel oops.

NULL Pointer Dereference

Ubuntu 6.8 AppArmor Socket Mediation Uninitialized Variable
CVE-2026-47336 3.3 - Low - May 28, 2026

Ubuntu Linux 6.8 contains SAUCE patches with a possible use of an uninitialized variable in AppArmor AF_INET/AF_INET6 socket mediation code. The bug can be triggered by an unprivileged local user and could result in incorrect fine-grained mediation of network sockets.

Use of Uninitialized Variable

Ubuntu 6.8: Null Deref in AppArmor SAUCE, Local Kernel Panic
CVE-2026-47335 5.5 - Medium - May 28, 2026

Ubuntu Linux 6.8 contains SAUCE patches with a possible NULL pointer dereference in the handling of AppArmor notifications. The bug can be triggered by an unprivileged local user. This can lead to a kernel panic.

NULL Pointer Dereference

AppArmor SAUCE bug in Ubuntu kernel 6.8/6.17/7.0 causes panic/deadlock
CVE-2026-47334 5.5 - Medium - May 28, 2026

Ubuntu Linux 6.8, 6.17 and 7.0 contain AppArmor SAUCE patches which incorrectly sleep while holding a spinlock in notification handling code. The bug can be triggered by an unprivileged local user and can result in kernel panic or deadlock.

Deadlock

Ubuntu Linux 6.8/6.17/7.0 AppArmor SAUCE OOB Heap Read via buffer size miscalc
CVE-2026-47333 7.8 - High - May 28, 2026

Ubuntu Linux 6.8, 6.17 and 7.0 contain AppArmor SAUCE patches which can potentially incorrectly compute the size of an internal buffer, leading to a heap memory out-of-bounds read in notification handling code. The bug can be triggered by an unprivileged local user and can result in invalid data being processed by the AppArmor DFA policy engine.

Out-of-bounds Read

Ubuntu Linux 6.8,6.17,7.0 AppArmor SAUCE OOB Read Vulnerability
CVE-2026-47332 5.5 - Medium - May 28, 2026

Ubuntu Linux 6.8, 6.17 and 7.0 contain AppArmor SAUCE patches which incorrectly validate the size of an internal structure, leading to an out-of-bounds read in notification handling code. The bug can be triggered by an unprivileged local user and can result in information disclosure from adjacent slab objects.

Out-of-bounds Read

AppArmor SAUCE UAF in Ubuntu 6.8 kernel due to missing lock
CVE-2026-47331 7.8 - High - May 28, 2026

Ubuntu Linux 6.8 contains AppArmor SAUCE patches which fail to acquire a lock when modifying a linked list. An unprivileged local user could trigger the race condition that can lead to a use-after-free (UAF) and, theoretically, arbitrary code execution.

Dangling pointer

Ubuntu AppArmor SAUCE Uninit Var Bug (6.8/7.x) Wrong Caching
CVE-2026-47330 3.3 - Low - May 28, 2026

Ubuntu Linux 6.8, 7.17 and 7.0 contain AppArmor SAUCE patches which can, under certain circumstances, use an uninitialized variable in notification handling code. The bug can be triggered by an unprivileged local user and can result in the incorrect caching of AppArmor notification responses.

Use of Uninitialized Variable

Local User Crafted AppAmor Name Field in Ubuntu 6.8/6.17/7.0 SAUCE
CVE-2026-47329 3.3 - Low - May 28, 2026

Ubuntu Linux 6.8, 6.17 and 7.0 contain SAUCE patches which fail to validate invalid sizes of the name field in AppAmor notification responses. The bug can be triggered by an unprivileged local user and could result in handling of crafted responses.

Improper Validation of Specified Quantity in Input

Ubuntu 6.8/6.17/7.0 AppArmor SAUCE Pointer Free CVE-2026-47328
CVE-2026-47328 6.1 - Medium - May 28, 2026

Ubuntu Linux 6.8, 6.17 and 7.0 contain AppArmor SAUCE patches which incorrectly attempt to free a pointer which was not previously kmalloc()d, while at the same time leaking allocated memory. The bug can be triggered by an unprivileged local user and can result in the corruption of slab metadata and could lead to resource exhaustion.

Free of Memory not on the Heap

Ubuntu Kernel 6.87.0 NULL Deref in AppArmor (Local) fixed 7.1
CVE-2026-47327 3.3 - Low - May 28, 2026

Ubuntu Linux 6.8, 6.17 and 7.0 contain SAUCE patches with a possible NULL pointer dereference in the handling of AppArmor notifications. The bug can be triggered by an unprivileged local user. This can lead to a kernel oops.

NULL Pointer Dereference

AppArmor SAUCE memory leak causing resource exhaustion in Ubuntu 6.8/6.17/7.0
CVE-2026-47326 5.5 - Medium - May 28, 2026

Ubuntu Linux 6.8, 6.17 and 7.0 contain SAUCE patches with a memory leak in the handling of big responses to AppArmor notifications. The bug can be triggered by an unprivileged local user. The memory leak could lead to resource exhaustion.

Memory Leak

Samba Remote Cmd Exec via Unsanitized %u in check password script
CVE-2026-4408 9 - Critical - May 28, 2026

A flaw was found in Samba. A remote attacker can exploit a misconfiguration in Samba file servers and classic domain controllers that use the "check password script" feature. If this script is configured with the %u substitution character, the client-controlled username is passed without proper escaping of shell meta-characters. This vulnerability allows an attacker to achieve remote command execution on the affected system. This issue primarily affects non-standard configurations where the "check password script" is used with %u and the samba-dcerpcd service is started as a system service.

Shell injection

Linux Kernel AEAD AIO IV Snapshot Vulnerability
CVE-2026-46028 - May 27, 2026

In the Linux kernel, the following vulnerability has been resolved: crypto: algif_aead - snapshot IV for async AEAD requests AF_ALG AEAD AIO requests currently use the socket-wide IV buffer during request processing. For async requests, later socket activity can update that shared state before the original request has fully completed, which can lead to inconsistent IV handling. Snapshot the IV into per-request storage when preparing the AEAD request, so in-flight operations no longer depend on mutable socket state.

Linux Kernel RxRPC Decrypt Packet Leakage Vulnerability (CVE-2026-46000)
CVE-2026-46000 - May 27, 2026

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix conn-level packet handling to unshare RESPONSE packets The security operations that verify the RESPONSE packets decrypt bits of it in place - however, the sk_buff may be shared with a packet sniffer, which would lead to the sniffer seeing an apparently corrupt packet (actually decrypted). Fix this by handing a copy of the packet off to the specific security handler if the packet was cloned.

Linux Kernel rxrpc: UAF Fix after skb_unshare() failure
CVE-2026-45998 - May 27, 2026

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix potential UAF after skb_unshare() failure If skb_unshare() fails to unshare a packet due to allocation failure in rxrpc_input_packet(), the skb pointer in the parent (rxrpc_io_thread()) will be NULL'd out. This will likely cause the call to trace_rxrpc_rx_done() to oops. Fix this by moving the unsharing down to where rxrpc_input_call_event() calls rxrpc_input_call_packet(). There are a number of places prior to that where we ignore DATA packets for a variety of reasons (such as the call already being complete) for which an unshare is then avoided. And with that, rxrpc_input_packet() doesn't need to take a pointer to the pointer to the packet, so change that to just a pointer.

Samba NTFS Reparse Points Access Control Bypass via SMB
CVE-2026-1933 7.1 - High - May 27, 2026

A flaw was found in Sambas handling of NTFS-style reparse points on shares configured with read only = yes. Due to missing SMB-layer access checks, authenticated users with underlying filesystem write permissions may create or delete reparse point metadata through SMB operations even on read-only exports. This could allow modification of SMB-visible file behavior, including converting files into symbolic links or other reparse point types.

Authorization

AppArmor NULL ptr deref in __unix_needs_revalidation (Linux kernel)
CVE-2026-45966 - May 27, 2026

In the Linux kernel, the following vulnerability has been resolved: apparmor: fix NULL pointer dereference in __unix_needs_revalidation When receiving file descriptors via SCM_RIGHTS, both the socket pointer and the socket's sk pointer can be NULL during socket setup or teardown, causing NULL pointer dereferences in __unix_needs_revalidation(). This is a regression in AppArmor 5.0.0 (kernel 6.17+) where the new __unix_needs_revalidation() function was added without proper NULL checks. The crash manifests as: BUG: kernel NULL pointer dereference, address: 0x0000000000000018 RIP: aa_file_perm+0xb7/0x3b0 (or +0xbe/0x3b0, +0xc0/0x3e0) Call Trace: apparmor_file_receive+0x42/0x80 security_file_receive+0x2e/0x50 receive_fd+0x1d/0xf0 scm_detach_fds+0xad/0x1c0 The function dereferences sock->sk->sk_family without checking if either sock or sock->sk is NULL first. Add NULL checks for both sock and sock->sk before accessing sk_family.

Sambas vfs_worm Rename Bypass Enables Overwrite of WORM Files
CVE-2026-2340 6.5 - Medium - May 27, 2026

A flaw was found in Sambas vfs_worm module. The module is intended to provide write-once, read-many (WORM) protections by preventing modification of files after a configurable grace period. Due to insufficient validation during rename operations, an authenticated user with write access to a share could overwrite a protected file by renaming a newly created file over the existing WORM-protected file.

Improper Handling of Insufficient Permissions or Privileges

Samba CA AutoEnroll HTTP Trust Misinstall (CVE-2026-3012)
CVE-2026-3012 8 - High - May 27, 2026

A flaw was found in Sambas certificate auto-enrollment Group Policy handling. When certificate auto-enrollment is enabled, Samba may retrieve a CA certificate over an unencrypted HTTP connection and install it into the local trust store without proper verification. An attacker with the ability to intercept or redirect network traffic could exploit this behavior to supply a malicious certificate authority certificate, potentially allowing interception or spoofing of trusted communications.

Insufficient Verification of Data Authenticity

GnuTLS PKCS#12 Bag Off-by-One Buffer Overwrite
CVE-2026-42015 5.3 - Medium - May 26, 2026

A flaw was found in gnutls. An off-by-one error exists in the PKCS#12 bag element bounds check. This vulnerability allows an remote attacker to write past the internal array of a PKCS#12 bag when appending to a bag that already contains 32 elements. This memory corruption could lead to a denial of service (DoS) or potentially other unspecified impacts.

off-by-five

GnuTLS SAN Size ForkCheck Bypass
CVE-2026-42013 8.2 - High - May 26, 2026

A flaw was found in gnutls. When validating certificates, an oversized Subject Alternative Name (SAN) could cause the validation process to incorrectly fall back to checking the Common Name (CN) field. This could allow a remote attacker to bypass proper certificate validation, potentially leading to spoofing or man-in-the-middle attacks.

Improper Validation of Specified Quantity in Input

GNUTLS Certificate Validation Bypass via URI/SRV SAN Fallback
CVE-2026-42012 7.1 - High - May 26, 2026

A flaw was found in gnutls. A remote attacker could exploit this vulnerability by presenting a specially crafted certificate that contains Uniform Resource Identifier (URI) or Service (SRV) Subject Alternative Names (SANs). This could cause the certificate validation process to incorrectly fall back to checking DNS hostnames against the Common Name (CN), potentially allowing the attacker to spoof legitimate services or intercept sensitive information.

Improper Certificate Validation

Libgnutls RSA PKCS#11 Key Exchange Overread Info Disclosure
CVE-2026-5260 8.2 - High - May 26, 2026

A flaw was found in libgnutls. A remote attacker, by sending an extremely short premaster secret during an RSA key exchange to a server using an RSA key backed by a PKCS#11 token, could trigger a short heap overread. This memory corruption vulnerability could lead to information disclosure.

Improper Validation of Specified Quantity in Input

Shell Injection in Samba Print Service via Unescaped %J
CVE-2026-4480 9 - Critical - May 26, 2026

A flaw was found in the Samba printing subsystem. Samba passes the client-controlled job description string to the command configured with the "print command" setting via the "%J" substitution character without escaping shell meta characters. A remote attacker could exploit this vulnerability by sending a specially crafted print job description that contains unescaped shell characters. This could lead to remote code execution on the affected system.

Shell injection

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