CVE-2026-11610 vulnerability in Red Hat Products
Published on July 7, 2026
389-ds-base: 389-ds-base: heap buffer overflow in sasl_io_recv() via padded sasl unbind
A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server
(389-ds-base). After a successful SASL bind with integrity protection (SSF > 0),
an authenticated attacker can send a specially crafted oversized LDAP UNBIND packet
that is copied into a 512-byte heap receive buffer without a bounds check in
sasl_io_recv() in sasl_io.c. This allows up to approximately 2 megabytes of
attacker-controlled data to overflow the buffer, causing a denial of service (server
crash). In FreeIPA and Red Hat Identity Management deployments, any domain user with
a valid Kerberos ticket, any enrolled host, or any service account can trigger this
vulnerability over the network after authenticating via GSSAPI.
The vulnerable code path has existed since approximately 2013 (389-ds-base 1.3.2) and
was not addressed by the CVE-2025-14905 fix, which patched a separate heap overflow
in schema.c only.
Vulnerability Analysis
CVE-2026-11610 is exploitable with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.
Timeline
Reported to Red Hat.
Made public. 76 days later.
Weakness Type
Heap-based Buffer Overflow
A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
Products Associated with CVE-2026-11610
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