Cyber Resilience

CVE-2025-21814

Memory Safety in Linux Kernel 3.0 – 6.1.129

Published
27 February 2025
Modified
14 July 2026
Patch / advisory
CVSS Score v3.1 5.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0022 13th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2025-21814 is a medium-severity NULL Pointer Dereference (CWE-476) vulnerability in Linux Linux Kernel. Its CVSS base score is 5.5 (Medium).

Operationally, ranked at the 13th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SI-11 (Error Handling) and SA-11 (Developer Testing and Evaluation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

In the Linux kernel, the following vulnerability has been resolved: ptp: Ensure info->enable callback is always set The ioctl and sysfs handlers unconditionally call the ->enable callback. Not all drivers implement that callback, leading to NULL dereferences. Example of affected…

more

drivers: ptp_s390.c, ptp_vclock.c and ptp_mock.c. Instead use a dummy callback if no better was specified by the driver.

CWE(s)

Related Threats

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CVE-2025-22065Same product: Linux Linux Kernel

Affected Assets

linux
linux kernel
3.0 — 6.1.129 · 6.2 — 6.6.78 · 6.7 — 6.12.14

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-11 Error Handling
  • SA-11 Developer Testing and Evaluation
  • SA-15 Development Process, Standards, and Tools
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires the PTP core to handle a missing ->enable callback instead of performing an unconditional NULL dereference.

prevent

Developer testing and evaluation of both the PTP framework and affected drivers (ptp_s390, ptp_vclock, ptp_mock) would have identified the unconditional callback invocation.

prevent

Mandates use of secure development standards and tools that enforce safe defaults (always-present dummy callback) rather than allowing optional function pointers.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (static analysis, code review, safe coding standards) directly prevent NULL dereference bugs during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing can detect NULL dereference defects before release.

prevents

Secure SDLC mandates defensive coding practices that can prevent NULL dereferences.

prevents

Application security requirements can specify input validation and pointer-safety rules.

prevents

Secure architecture principles encourage defensive design that avoids unsafe pointer use.

prevents

Secure coding standards directly require NULL-pointer checks and safe dereference patterns.

References