SB20260912129 - Use-after-free in Linux kernel ceph
Published: September 12, 2026
Security Bulletin ID
SB20260912129
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-89654)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a use-after-free.
The vulnerability exists due to missing session reference counting in check_new_map() when processing MDS session map updates. A local user can trigger a race between session map processing and session teardown to cause a use-after-free.
Remediation
Install update from vendor's website.