Observable discrepancy in Linux kernel - CVE-2026-31781
Published: May 2, 2026
Vulnerability identifier: #VU128915
CSH Severity: Low
CVSS v4.0: 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/E:U/U:Clear
CVE-ID: CVE-2026-31781
CWE-ID: CWE-203
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to improper restriction of speculative execution in drm_compat_ioctl when processing a user-controlled pointer used as an index into a function pointer table. A local user can supply a crafted index value to disclose sensitive information.
The issue affects the drm compat ioctl path.
How to mitigate CVE-2026-31781
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/27ef84bba9b9d7b03418c60fbc6069ea0e87b13c
- https://git.kernel.org/stable/c/46a60ee8956ef1975f00455f614761c7ecedc09d
- https://git.kernel.org/stable/c/489f2ef2b908898d01df697dc4fe1476674be640
- https://git.kernel.org/stable/c/4a41c2b18fc05d30b718d2602cac339eae710b34
- https://git.kernel.org/stable/c/5bb398991f378ef74d90b14a6ea8b61ff96cc03a
- https://git.kernel.org/stable/c/d59c5d8539662d95887b4564f3f72ad38076a2d5
- https://git.kernel.org/stable/c/f0e441be08a2eab10b2d06fccfa267ee599dd6b3
- https://git.kernel.org/stable/c/f8995c2df519f382525ca4bc90553ad2ec611067