CVE-2026-81666

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-81666
https://bugzilla.redhat.com/show_bug.cgi?id=2524923

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-04 10:17

Updated : 2026-09-08 19:08

NVD link : CVE-2026-81666

Mitre link : CVE-2026-81666

CVE.ORG link : CVE-2026-81666

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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