Improper input validation in Linux kernel - CVE-2026-31458
Published: April 24, 2026
Vulnerability identifier: #VU127687
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-31458
CWE-ID: CWE-20
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 privileged user to cause a denial of service.
The vulnerability exists due to improper input validation in damon_sysfs_handle_cmd() when handling sysfs commands after nr_contexts is set to 0. A local privileged user can write crafted values to sysfs control files to cause a denial of service.
The issue is triggered while DAMON is running, and commands other than OFF can dereference contexts_arr[0] after the contexts directory is made empty.
How to mitigate CVE-2026-31458
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/1bfe9fb5ed2667fb075682408b776b5273162615
- https://git.kernel.org/stable/c/1e8da792672481d603fa7cd0d815577220a3ee27
- https://git.kernel.org/stable/c/708033c231bd782858f4ddbb46ee874a5a5fbdab
- https://git.kernel.org/stable/c/aba546061341b56e9ffb37e1eb661a3628b6ec12
- https://git.kernel.org/stable/c/bbe03ad3fb9e714191757ca7b41582f930be7be2