CVE-2026-81666 (GCVE-0-2026-81666)

Vulnerability from cvelistv5 – Published: 2026-09-04 09:46 – Updated: 2026-09-08 14:41
VLAI
Title
Corosync: corosync: integer overflow in check_memb_commit_token_sanity may bypass message length validation on 32-bit systems
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 14:41 UTC
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1039 records in the last 180 days details
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-81666 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2524923 issue-trackingx_refsource_REDHAT
Impacted products
Date Public
2026-09-04 08:14
Credits
Red Hat would like to thank Tristan Madani (Talence Security) for reporting this issue.
Show details on NVD website
To clipboard 

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