CVE-2026-107161 (GCVE-0-2026-107161)

Vulnerability from cvelistv5 – Published: 2026-10-07 19:29 – Updated: 2026-10-07 19:29
VLAI
Title
Cyrus-sasl: heap buffer overflow in cyrus-sasl add_to_challenge() allows malicious server to crash or compromise digest-md5 clients
Summary
A heap-based buffer overflow flaw was found in Cyrus SASL. The add_to_challenge() function in the DIGEST-MD5 plugin computes the size of the buffer needed for a challenge/response field before DIGEST-MD5 quoting is applied, but does not recompute that size when quoting (escaping special characters) makes the value longer. The under-sized buffer is then passed to strcat(), causing a heap-based out-of-bounds write whose size depends on attacker-controlled input. A malicious or on-path DIGEST-MD5 (or HTTP Digest) server can trigger this flaw in a connecting client by supplying a crafted challenge field, such as realm or nonce, most likely resulting in a crash of the client application.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
  • CWE-122 - Heap-based Buffer Overflow
Assigner
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-107161 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2460420 issue-trackingx_refsource_REDHAT
Impacted products
Date Public
2026-10-07 17:53
Credits
This issue was discovered by Bruno Fournier and Found by AISLE in partnership with Red Hat.
Show details on NVD website
To clipboard 

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