Buffer overflow in Red Hat Enterprise Linux 10

CVE-2026-107161

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.

Vulnerability class: Buffer Overflow

Published .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-107161?
CVE-2026-107161 is a high-severity vulnerability in Red Hat Enterprise Linux 10, classified under Heap-based Buffer Overflow. CVSS score: 7.5/10. Published 2026-10-07.
How severe is CVE-2026-107161?
High severity. CVSS v3 base score is 7.5 out of 10.