Vulnerability Database

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Total vulnerabilities in the database

CVE-2025-71135 — linux / linux_kernel

NULL Pointer Dereference

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: Jan 14, 2026
  • Updated: Mar 26, 2026
  • CVE: CVE-2025-71135
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Medium
  • Score: 5.5
  • AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CWEs:

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Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

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