NULL pointer dereference in Linux

CVE-2025-71135

In the Linux kernel, the following vulnerability has been resolved: md/raid5: fix possible null-pointer dereferences in raid5_store_group_thread_cnt() The variable mddev->private is first assigned to conf and then checked: conf = mddev->private; if (!conf) ... If conf is NULL, then mddev->private is also NULL. In this case, null-pointer dereferences can occur when calling raid5_quiesce(): raid5_quiesce(mddev, true); raid5_quiesce(mddev, false); since mddev->private is assigned to conf again in raid5_quiesce(), and conf is dereferenced in several places, for example: conf->quiesce = 0; wake_up(&conf->wait_for_quiescent); To fix this issue, the function should unlock mddev and return before invoking raid5_quiesce() when conf is NULL, following the existing pattern in raid5_change_consistency_policy().

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.002 (5.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 5.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-71135: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

  • Linux — versions fa1944bbe6220eb929e2c02e5e8706b908565711, be19e6e4339d1579d5f2fae8ce4facf9521dbbfc, 6.12.4
  • Linux Kernel — versions 6.13, 6.19

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-71135?
CVE-2025-71135 is a medium-severity vulnerability in Linux, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2026-01-14.
How severe is CVE-2025-71135?
Medium severity. CVSS v3 base score is 5.5 out of 10.