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Products by OpenBSD Sorted by Most Security Vulnerabilities since 2018

OpenBSD OpenSSH49 vulnerabilities
SSH Server Implementation

OpenBSD43 vulnerabilities

OpenBSD LibreSSL6 vulnerabilities
Crypto Library

OpenBSD Opensmtpd1 vulnerability

Known Exploited OpenBSD Vulnerabilities

The following OpenBSD vulnerabilities have been marked by CISA as Known to be Exploited by threat actors.

Title Description Added
OpenSMTPD Remote Code Execution Vulnerability smtp_mailaddr in smtp_session.c in OpenSMTPD, as used in OpenBSD and other products, allows remote attackers to execute arbitrary commands as root via a crafted SMTP session. CVE-2020-7247 March 25, 2022

By the Year

In 2024 there have been 0 vulnerabilities in OpenBSD . Last year OpenBSD had 13 security vulnerabilities published. Right now, OpenBSD is on track to have less security vulnerabilities in 2024 than it did last year.

Year Vulnerabilities Average Score
2024 0 0.00
2023 13 7.44
2022 3 6.23
2021 6 6.28
2020 5 8.16
2019 12 7.38
2018 6 5.95

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

Recent OpenBSD Security Vulnerabilities

OpenSSH through 9.6, when common types of DRAM are used, might

CVE-2023-51767 7 - High - December 24, 2023

OpenSSH through 9.6, when common types of DRAM are used, might allow row hammer attacks (for authentication bypass) because the integer value of authenticated in mm_answer_authpassword does not resist flips of a single bit. NOTE: this is applicable to a certain threat model of attacker-victim co-location in which the attacker has user privileges.

In ssh-agent in OpenSSH before 9.6, certain destination constraints can be incompletely applied

CVE-2023-51384 5.5 - Medium - December 18, 2023

In ssh-agent in OpenSSH before 9.6, certain destination constraints can be incompletely applied. When destination constraints are specified during addition of PKCS#11-hosted private keys, these constraints are only applied to the first key, even if a PKCS#11 token returns multiple keys.

In ssh in OpenSSH before 9.6

CVE-2023-51385 6.5 - Medium - December 18, 2023

In ssh in OpenSSH before 9.6, OS command injection might occur if a user name or host name has shell metacharacters, and this name is referenced by an expansion token in certain situations. For example, an untrusted Git repository can have a submodule with shell metacharacters in a user name or host name.

Shell injection

The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such

CVE-2023-48795 5.9 - Medium - December 18, 2023

The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the extension negotiation message), and a client and server may consequently end up with a connection for which some security features have been downgraded or disabled, aka a Terrapin attack. This occurs because the SSH Binary Packet Protocol (BPP), implemented by these extensions, mishandles the handshake phase and mishandles use of sequence numbers. For example, there is an effective attack against SSH's use of ChaCha20-Poly1305 (and CBC with Encrypt-then-MAC). The bypass occurs in chacha20-poly1305@openssh.com and (if CBC is used) the -etm@openssh.com MAC algorithms. This also affects Maverick Synergy Java SSH API before 3.1.0-SNAPSHOT, Dropbear through 2022.83, Ssh before 5.1.1 in Erlang/OTP, PuTTY before 0.80, AsyncSSH before 2.14.2, golang.org/x/crypto before 0.17.0, libssh before 0.10.6, libssh2 through 1.11.0, Thorn Tech SFTP Gateway before 3.4.6, Tera Term before 5.1, Paramiko before 3.4.0, jsch before 0.2.15, SFTPGo before 2.5.6, Netgate pfSense Plus through 23.09.1, Netgate pfSense CE through 2.7.2, HPN-SSH through 18.2.0, ProFTPD before 1.3.8b (and before 1.3.9rc2), ORYX CycloneSSH before 2.3.4, NetSarang XShell 7 before Build 0144, CrushFTP before 10.6.0, ConnectBot SSH library before 2.2.22, Apache MINA sshd through 2.11.0, sshj through 0.37.0, TinySSH through 20230101, trilead-ssh2 6401, LANCOM LCOS and LANconfig, FileZilla before 3.66.4, Nova before 11.8, PKIX-SSH before 14.4, SecureCRT before 9.4.3, Transmit5 before 5.10.4, Win32-OpenSSH before 9.5.0.0p1-Beta, WinSCP before 6.2.2, Bitvise SSH Server before 9.32, Bitvise SSH Client before 9.33, KiTTY through 0.76.1.13, the net-ssh gem 7.2.0 for Ruby, the mscdex ssh2 module before 1.15.0 for Node.js, the thrussh library before 0.35.1 for Rust, and the Russh crate before 0.40.2 for Rust.

Improper Validation of Integrity Check Value

OpenBSD 7.3 before errata 014 is missing an argument-count bounds check in console terminal emulation

CVE-2023-40216 5.5 - Medium - August 10, 2023

OpenBSD 7.3 before errata 014 is missing an argument-count bounds check in console terminal emulation. This could cause incorrect memory access and a kernel crash after receiving crafted DCS or CSI terminal escape sequences.

AuthZ

The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently trustworthy search path

CVE-2023-38408 9.8 - Critical - July 20, 2023

The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently trustworthy search path, leading to remote code execution if an agent is forwarded to an attacker-controlled system. (Code in /usr/lib is not necessarily safe for loading into ssh-agent.) NOTE: this issue exists because of an incomplete fix for CVE-2016-10009.

Unquoted Search Path or Element

A double free or use after free could occur after SSL_clear in OpenBSD 7.2 before errata 026 and 7.3 before errata 004

CVE-2023-35784 9.8 - Critical - June 16, 2023

A double free or use after free could occur after SSL_clear in OpenBSD 7.2 before errata 026 and 7.3 before errata 004, and in LibreSSL before 3.6.3 and 3.7.x before 3.7.3. NOTE: OpenSSL is not affected.

Double-free

x509/x509_verify.c in LibreSSL before 3.4.2, and OpenBSD before 7.0 errata 006

CVE-2021-46880 9.8 - Critical - April 15, 2023

x509/x509_verify.c in LibreSSL before 3.4.2, and OpenBSD before 7.0 errata 006, allows authentication bypass because an error for an unverified certificate chain is sometimes discarded.

Improper Certificate Validation

An issue was discovered in x509/x509_verify.c in LibreSSL before 3.6.1, and in OpenBSD before 7.2 errata 001

CVE-2022-48437 5.3 - Medium - April 12, 2023

An issue was discovered in x509/x509_verify.c in LibreSSL before 3.6.1, and in OpenBSD before 7.2 errata 001. x509_verify_ctx_add_chain does not store errors that occur during leaf certificate verification, and therefore an incorrect error is returned. This behavior occurs when there is an installed verification callback that instructs the verifier to continue upon detecting an invalid certificate.

Improper Certificate Validation

ascii_load_sockaddr in smtpd in OpenBSD before 7.1 errata 024 and 7.2 before errata 020, and OpenSMTPD Portable before 7.0.0-portable commit f748277, can abort upon a connection

CVE-2023-29323 7.8 - High - April 04, 2023

ascii_load_sockaddr in smtpd in OpenBSD before 7.1 errata 024 and 7.2 before errata 020, and OpenSMTPD Portable before 7.0.0-portable commit f748277, can abort upon a connection from a local, scoped IPv6 address.

ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints

CVE-2023-28531 9.8 - Critical - March 17, 2023

ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.

In OpenBSD 7.2, a TCP packet with destination port 0

CVE-2023-27567 7.5 - High - March 03, 2023

In OpenBSD 7.2, a TCP packet with destination port 0 that matches a pf divert-to rule can crash the kernel.

OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling

CVE-2023-25136 6.5 - Medium - February 03, 2023

OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states "remote code execution is theoretically possible."

Double-free

slaacd in OpenBSD 6.9 and 7.0 before 2022-03-22 has an integer signedness error and resultant heap-based buffer overflow triggerable by a crafted IPv6 router advertisement

CVE-2022-27882 7.5 - High - March 25, 2022

slaacd in OpenBSD 6.9 and 7.0 before 2022-03-22 has an integer signedness error and resultant heap-based buffer overflow triggerable by a crafted IPv6 router advertisement. NOTE: privilege separation and pledge can prevent exploitation.

Incorrect Conversion between Numeric Types

engine.c in slaacd in OpenBSD 6.9 and 7.0 before 2022-02-21 has a buffer overflow triggerable by an IPv6 router advertisement with more than seven nameservers

CVE-2022-27881 7.5 - High - March 25, 2022

engine.c in slaacd in OpenBSD 6.9 and 7.0 before 2022-02-21 has a buffer overflow triggerable by an IPv6 router advertisement with more than seven nameservers. NOTE: privilege separation and pledge can prevent exploitation.

Classic Buffer Overflow

An issue was discovered in OpenSSH before 8.9

CVE-2021-36368 3.7 - Low - March 13, 2022

An issue was discovered in OpenSSH before 8.9. If a client is using public-key authentication with agent forwarding but without -oLogLevel=verbose, and an attacker has silently modified the server to support the None authentication option, then the user cannot determine whether FIDO authentication is going to confirm that the user wishes to connect to that server, or that the user wishes to allow that server to connect to a different server on the user's behalf. NOTE: the vendor's position is "this is not an authentication bypass, since nothing is being bypassed.

authentification

sshd in OpenSSH 6.2 through 8.x before 8.8, when certain non-default configurations are used

CVE-2021-41617 7 - High - September 26, 2021

sshd in OpenSSH 6.2 through 8.x before 8.8, when certain non-default configurations are used, allows privilege escalation because supplemental groups are not initialized as expected. Helper programs for AuthorizedKeysCommand and AuthorizedPrincipalsCommand may run with privileges associated with group memberships of the sshd process, if the configuration specifies running the command as a different user.

x509_constraints_parse_mailbox in lib/libcrypto/x509/x509_constraints.c in LibreSSL through 3.4.0 has a stack-based buffer over-read

CVE-2021-41581 5.5 - Medium - September 24, 2021

x509_constraints_parse_mailbox in lib/libcrypto/x509/x509_constraints.c in LibreSSL through 3.4.0 has a stack-based buffer over-read. When the input exceeds DOMAIN_PART_MAX_LEN, the buffer lacks '\0' termination.

Out-of-bounds Read

OpenSSH through 8.7 allows remote attackers, who have a suspicion

CVE-2016-20012 5.3 - Medium - September 15, 2021

OpenSSH through 8.7 allows remote attackers, who have a suspicion that a certain combination of username and public key is known to an SSH server, to test whether this suspicion is correct. This occurs because a challenge is sent only when that combination could be valid for a login session. NOTE: the vendor does not recognize user enumeration as a vulnerability for this product

It was found in FreeBSD 8.0, 6.3 and 4.9, and OpenBSD 4.6

CVE-2010-4816 7.5 - High - June 22, 2021

It was found in FreeBSD 8.0, 6.3 and 4.9, and OpenBSD 4.6 that a null pointer dereference in ftpd/popen.c may lead to remote denial of service of the ftpd service.

NULL Pointer Dereference

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