Cyber Resilience

CVE-2026-35359

Race Condition in Uutils Coreutils

Public PoCRace Condition
Published
22 April 2026
Modified
24 April 2026
Patch / advisory
CVSS Score v3.1 4.7
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0010 1th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-35359 is a medium-severity Link Following (CWE-59) vulnerability in Uutils Coreutils. Its CVSS base score is 4.7 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 1th 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 AC-3 (Access Enforcement) and SI-2 (Flaw Remediation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A Time-of-Check to Time-of-Use (TOCTOU) vulnerability in the cp utility of uutils coreutils allows an attacker to bypass no-dereference intent. The utility checks if a source path is a symbolic link using path-based metadata but subsequently opens it without the…

more

O_NOFOLLOW flag. An attacker with concurrent write access can swap a regular file for a symbolic link during this window, causing a privileged cp process to copy the contents of arbitrary sensitive files into a destination controlled by the attacker.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

TOCTOU race in privileged cp enables unauthorized sensitive file reads via symlink swap, directly facilitating local privilege escalation.

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

CVEs Like This One

CVE-2026-35352Same product: Uutils Coreutils
CVE-2026-35356Same product: Uutils Coreutils
CVE-2026-35362Same product: Uutils Coreutils
CVE-2026-35355Same product: Uutils Coreutils
CVE-2026-35370Same product: Uutils Coreutils
CVE-2026-35372Same product: Uutils Coreutils
CVE-2026-35361Same product: Uutils Coreutils
CVE-2026-35349Same product: Uutils Coreutils
CVE-2026-35360Same product: Uutils Coreutils
CVE-2026-35365Same product: Uutils Coreutils

Affected Assets

uutils
coreutils
all versions

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • SI-2 Flaw Remediation
  • AC-6 Least Privilege
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V15.4.2
  • V17.2.6

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces the no-dereference policy on file operations that the TOCTOU race bypasses.

prevent

Requires timely remediation of the identified TOCTOU flaw (CWE-367/59) in the cp utility.

prevent

Limits the files a privileged cp process can read, reducing impact if the symlink swap succeeds.

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 code to validate paths and avoid unsafe link following.

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 link-following flaws before release.

prevents

Secure SDLC practices can mandate link-resolution checks and canonicalization before file access.

prevents

Application security requirements can explicitly require safe handling of symbolic links and path traversal.

prevents

Secure architecture principles include input validation and safe file-access design patterns.

prevents

Secure coding standards directly address canonicalization and symlink attacks during implementation.

none

Reliable, synchronized time across systems narrows the exploitable window in which a resource state can change between a security check and its use.

References