LiveActive security incident?Get immediate response
CVE Record

CVE-2025-71135: md/raid5: fix possible null-pointer dereferences in raid5_store_group_thread_cnt()

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().

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

This is a Linux kernel md/RAID5 bug where a missing null check can lead to a kernel null-pointer dereference. The practical impact is not fully scored in the provided sources, but kernel null dereferences commonly create availability risk. There is no provided evidence of active exploitation.

Executive priority

Prioritize assessment for production Linux servers using software RAID5, especially where uptime is critical. Without exploitation evidence or severity scoring, this is not a broad emergency, but kernel fixes should move through normal patch governance promptly.

Technical view

The issue is in raid5_store_group_thread_cnt(). mddev->private is assigned to conf and checked, but raid5_quiesce() can later re-read and dereference mddev->private when it is NULL. The upstream fix returns before raid5_quiesce() when conf is NULL, matching an existing kernel pattern.

Likely exposure

Exposure appears limited to Linux systems using the md RAID5 kernel path. The version data in the bundle is incomplete or ambiguous, so teams should verify against their distribution kernel advisories and whether referenced stable fixes are backported.

Exploitation context

The bundle does not provide exploit details, CVSS, CWE, or confirmed attack prerequisites. It also marks KEV as false. Treat this as a kernel availability concern until vendor advisories clarify reachability and impact.

Researcher notes

The strongest evidence is the kernel commit rationale: conf may be NULL and raid5_quiesce() dereferences mddev->private. The source bundle does not establish user reachability, privilege requirements, crash reliability, or affected distro package ranges.

Mitigation direction

  • Inventory Linux hosts using md RAID5 functionality.
  • Check vendor or distribution advisories for CVE-2025-71135 coverage.
  • Update to a kernel package containing the referenced stable fix.
  • Validate backported fixes instead of relying only on version strings.
  • Monitor kernel.org and distribution guidance for impact clarifications.

Validation and detection

  • Identify systems with Linux md RAID5 configured or available.
  • Compare installed kernel builds against vendor CVE guidance.
  • Review kernel changelogs for the raid5_store_group_thread_cnt fix.
  • Confirm whether referenced stable commits are present or backported.
  • Document unsupported or self-built kernels for separate review.
Prepared
Confidence
medium
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2025-71135 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
0ADP providers
4Source links

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxbe19e6e4339d1579d5f2fae8ce4facf9521dbbfc, fa1944bbe6220eb929e2c02e5e8706b908565711, fa1944bbe6220eb929e2c02e5e8706b908565711, 6.12.4unaffected
LinuxLinux6.13, 0, 6.12.64, 6.18.4, 6.19affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.