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  4. CVE 2025 21978 drmhyperv fix address space leak when hyper v drm
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Back to active CVEs
Medium · CVSS 5.5CVE-2025-21978

drm/hyperv: Fix address space leak when Hyper-V DRM device is removedCVE-2025-21978

Answer in brief

CVE-2025-21978 records a Medium severity (CVSS 5.5) vulnerability in drm/hyperv: Fix address space leak when Hyper-V DRM device is removed. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Apr 1, 2025Updated Nov 5, 2026Source checked Nov 5, 2026First seen by HOL Nov 5, 2026Material review Nov 5, 2026
Upstream Advisory

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
CWE-401
Source
CVE List V5
Source checked
Nov 5, 2026
References
6 linked sources
Open source record

Key facts

Risk
Medium · CVSS 5.5
Exploitation
Not marked as known exploited
Affected software
9 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Affected products and reported versions
ProductAffected versionsFixed versions
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:*Not reportedNot reported
Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Linux/Linuxgeneric>=a0ab5abced550ddeefddb06055ed60779a54eb79 <c40cd24bfb9bfbb315c118ca14ebe6cf52e2dd1e || >=a0ab5abced550ddeefddb06055ed60779a54eb79 <ad27b4a51495490b815580d9b935e8eee14d1a9c || >=a0ab5abced550ddeefddb06055ed60779a54eb79 <24f1bbfb2be77dad82489c1468bbb14312aab129 || >=a0ab5abced550ddeefddb06055ed60779a54eb79 <158242b56bf465a73e1edeac0fe828a8acad4499 || >=a0ab5abced550ddeefddb06055ed60779a54eb79 <aed709355fd05ef747e1af24a1d5d78cd7feb81ec40cd24bfb9bfbb315c118ca14ebe6cf52e2dd1e, ad27b4a51495490b815580d9b935e8eee14d1a9c, 24f1bbfb2be77dad82489c1468bbb14312aab129, 158242b56bf465a73e1edeac0fe828a8acad4499, aed709355fd05ef747e1af24a1d5d78cd7feb81e
Linux/Linuxgeneric6.0Not reported

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
  2. 2Review the reported fix. Update Linux/Linux to c40cd24bfb9bfbb315c118ca14ebe6cf52e2dd1e if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Apr 1, 2025

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Nov 5, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Nov 5, 2026

Sources and claim methodology

  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencelists.debian.org
Upstream source description

In the Linux kernel, the following vulnerability has been resolved: drm/hyperv: Fix address space leak when Hyper-V DRM device is removed When a Hyper-V DRM device is probed, the driver allocates MMIO space for the vram, and maps it cacheable. If the device removed, or in the error path for device probing, the MMIO space is released but no unmap is done. Consequently the kernel address space for the mapping is leaked. Fix this by adding iounmap() calls in the device removal path, and in the error path during device probing.

Quoted source text, attributed separately from HOL analysis.