CVE-2026-81666

medium

Description

An integer overflow was found in Corosync's handling of membership commit token messages. The length-validation check for these messages can be bypassed on 32-bit systems due to an integer overflow in the calculation of the expected message length, allowing a crafted network packet to trigger an out-of-bounds memory access that crashes the Corosync daemon. This results in a denial of service for the affected cluster node. The overflow does not occur on 64-bit systems, where the length calculation is correctly performed in 64-bit arithmetic.

References

https://bugzilla.redhat.com/show_bug.cgi?id=2524923

https://access.redhat.com/security/cve/CVE-2026-81666

Details

Source: Mitre, NVD

Published: 2026-09-04

Updated: 2026-09-04

Risk Information

CVSS v2

Base Score: 6.1

Vector: CVSS2#AV:A/AC:L/Au:N/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: Medium

EPSS

EPSS: 0.00271