[Debian-ha-maintainers] Bug#1133838: corosync: CVE-2026-35091

[Salvatore Bonaccorso]

Source: corosync
Version: CVE-2026-35092
Severity: grave
Tags: security upstream
Justification: user security hole
X-Debbugs-Cc: carnil at debian.org, Debian Security Team <team at security.debian.org>

Hi,

The following vulnerability was published for corosync.

CVE-2026-35091[0]:
| A flaw was found in Corosync. A remote unauthenticated attacker can
| exploit a wrong return value vulnerability in the Corosync
| membership commit token sanity check by sending a specially crafted
| User Datagram Protocol (UDP) packet. This can lead to an out-of-
| bounds read, causing a denial of service (DoS) and potentially
| disclosing limited memory contents. This vulnerability affects
| Corosync when running in totemudp/totemudpu mode, which is the
| default configuration.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-35091
    https://www.cve.org/CVERecord?id=CVE-2026-35091
[1] https://github.com/corosync/corosync/commit/a16614accfdb3481264d7281843fadf439d9ab1b

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore