Cyber Resilience

CVE-2025-66866

Gnu Binutils 2.26

Public PoC
Published
29 December 2025
Modified
14 January 2026
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0028 21th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2025-66866 is a high-severity Improper Input Validation (CWE-20) vulnerability in Gnu Binutils. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 21th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and SI-7 (Software, Firmware, and Information Integrity) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

An issue was discovered in function d_abi_tags in file cp-demangle.c in BinUtils 2.26 allows attackers to cause a denial of service via crafted PE file.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

DoS triggered by processing crafted PE input directly maps to application exploitation for endpoint DoS.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2025-66864Same product: Gnu Binutils
CVE-2025-69647Same product: Gnu Binutils
CVE-2025-11839Same product: Gnu Binutils
CVE-2025-66865Same product: Gnu Binutils
CVE-2025-11840Same product: Gnu Binutils
CVE-2025-69646Same product: Gnu Binutils
CVE-2025-66861Same product: Gnu Binutils
CVE-2025-66863Same product: Gnu Binutils
CVE-2025-11081Same product: Gnu Binutils
CVE-2025-69644Same product: Gnu Binutils

Affected Assets

gnu
binutils
2.26

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SI-7 Software, Firmware, and Information Integrity
  • SC-39 Process Isolation
Detect
Catch it (NIST detect / respond)
  • SI-7 Software, Firmware, and Information Integrity
Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces validation of all input data (here, PE file contents passed to d_abi_tags) before processing, blocking the malformed input that triggers the DoS.

preventdetect

Requires integrity verification of software and data (PE files) prior to use, detecting or rejecting the crafted input that exploits the demangler flaw.

prevent

Isolates processes that invoke BinUtils, limiting the blast radius of a DoS crash caused by the unvalidated PE file.

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 directly require and enforce input validation 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

Testing against a defined set of requirements and using code review plus vulnerability scanning forces validation of inputs and handling of unanticipated conditions, reducing the chance that malformed data will be accepted.

prevents

Secure-coding guidelines and mandatory security testing (including code scans) compel developers to validate and sanitize inputs at design and implementation time, lowering the incidence of malformed or malicious data reaching downstream components.

prevents

Mandating input controls that include integrity checks and input validation ensures that untrusted data is examined before use, blocking the root cause of many injection and malformed-data weaknesses.

prevents

Security-by-design principles explicitly call for data validation and sanitization at every layer, reducing the chance that malformed or malicious input will be processed without scrutiny.

prevents

Requiring language-specific secure coding standards, peer review, SAST and documented mitigation of common programming errors forces validation of all inputs before they are trusted.

none

Regular automated validation of system software and data content, combined with scanning of all inbound files, enforces input validation at the boundary before untrusted content is processed.

References