CVE-2026-31458

MEDIUM EPSS 2.3%
Published Apr 22, 20262mo ago · Modified Jun 17, 20262w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Apr 22, 2026 2mo ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: mm/damon/sysfs: check contexts->nr before accessing contexts_arr[0] Multiple sysfs command paths dereference contexts_arr[0] without first verifying that kdamond->contexts->nr == 1. A user can set nr_contexts to 0 via sysfs while DAMON is running, causing NULL pointer dereferences. In more detail, the issue can be triggered by privileged users like below. First, start DAMON and make contexts directory empty (kdamond->contexts->nr == 0). # damo start # cd /sys/kernel/mm/damon/admin/kdamonds/0 # echo 0 > contexts/nr_contexts Then, each of below commands will cause the NULL pointer dereference. # echo update_schemes_stats > state # echo update_schemes_tried_regions > state # echo update_schemes_tried_bytes > state # echo update_schemes_effective_quotas > state # echo update_tuned_intervals > state Guard all commands (except OFF) at the entry point of damon_sysfs_handle_cmd().

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
2.3% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-476 NULL Pointer Dereference Memory Safety

Affected Products 9

VendorProductVersionRange
linuxlinux_kernel*≥5.18  –  <6.6.131
linuxlinux_kernel*≥6.7  –  <6.12.80
linuxlinux_kernel*≥6.13  –  <6.18.21
linuxlinux_kernel*≥6.19  –  <6.19.11
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any
linuxlinux_kernel7.0any

References 5

  • git.kernel.org https://git.kernel.org/stable/c/1bfe9fb5ed2667fb075682408b776b5273162615
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/1e8da792672481d603fa7cd0d815577220a3ee27
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/708033c231bd782858f4ddbb46ee874a5a5fbdab
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/aba546061341b56e9ffb37e1eb661a3628b6ec12
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/bbe03ad3fb9e714191757ca7b41582f930be7be2
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/1bfe9fb5ed2667fb075682408b776b5273162615
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/1e8da792672481d603fa7cd0d815577220a3ee27
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/708033c231bd782858f4ddbb46ee874a5a5fbdab
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/aba546061341b56e9ffb37e1eb661a3628b6ec12
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/bbe03ad3fb9e714191757ca7b41582f930be7be2
    Patch