SB20260912128 - Out-of-bounds write in Linux kernel ceph
Published: September 12, 2026
Security Bulletin ID
SB20260912128
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Out-of-bounds write (CVE-ID: CVE-2026-89653)
CWE-ID: CWE-787 - Out-of-bounds write
CVSSv4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to cause an out-of-bounds write.
The vulnerability exists due to improper bounds checking in the fixed stack bitmap used by check_new_map() when processing a decoded MDSMap whose export_targets entries contain an out-of-range rank. A remote user can cause an MDSMap containing an out-of-range export target rank to be decoded to cause an out-of-bounds write.
Remediation
Install update from vendor's website.