Out-of-bounds write in Linux kernel - CVE-2026-89653
Published: September 12, 2026
Vulnerability identifier: #VU149151
CSH Severity: Low
CVSS v4: 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]
CVE-ID: CVE-2026-89653
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
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.
Affected software
Linux kernel
How to mitigate CVE-2026-89653
Install security update from vendor's repository.