Out-of-bounds read in Linux kernel - CVE-2026-89720
Published: September 12, 2026
Vulnerability identifier: #VU149086
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-89720
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to read beyond allocated memory.
The vulnerability exists due to an out-of-bounds read in ubifs_sb_verify_signature() when mounting a crafted signed UBIFS image. A local user can provide an image with an inflated signature length to read beyond allocated memory.
The signature is processed before it is cryptographically checked.
Affected software
Linux kernel
How to mitigate CVE-2026-89720
Install security update from vendor's repository.