Out-of-bounds read in Linux kernel - CVE-2026-89651
Published: September 12, 2026
Vulnerability identifier: #VU149149
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89651
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to an out-of-bounds read in the Ceph MDS client handle_session() function when processing MDSCapAuth records in a CEPH_SESSION_OPEN message. A remote attacker can send a specially crafted session-open message to cause a denial of service.
Only CEPH_SESSION_OPEN messages with a message version of 6 or later are affected.
Affected software
Linux kernel
How to mitigate CVE-2026-89651
Install security update from vendor's repository.