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 34 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

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 Path Interception (T1034); 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-25 (Reference Monitor) and AC-3 (Access Enforcement) — 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 Techniques

T1034 Path Interception Persistence
**This technique has been deprecated.
T1547.009 Shortcut Modification Persistence
Adversaries may create or modify shortcuts that can execute a program during system boot or user login.
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
T1574 Hijack Execution Flow Stealth
Adversaries may execute their own malicious payloads by hijacking the way operating systems run programs.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-35362Same product: Uutils Coreutils
CVE-2026-35355Same product: Uutils Coreutils
CVE-2026-35360Same product: Uutils Coreutils
CVE-2026-35353Same product: Uutils Coreutils
CVE-2026-35356Same product: Uutils Coreutils
CVE-2026-35352Same product: Uutils Coreutils
CVE-2026-35365Same product: Uutils Coreutils
CVE-2026-35349Same product: Uutils Coreutils
CVE-2026-35368Same product: Uutils Coreutils
CVE-2026-35372Same product: Uutils Coreutils

Affected Assets

uutils
coreutils
all versions

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

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

A reference monitor that is always invoked and analyzable structurally eliminates the non-atomic check-then-use pattern underlying TOCTOU.

Proper enforcement of access authorizations on the resolved target resource stops a link from reaching an unintended object.

Least-privilege limits the damage an attacker can cause after following an unintended link.

Process isolation limits the blast radius of a successful TOCTOU exploitation but does not remove the race itself.

Validating file-name inputs can reject or canonicalize names that resolve to links before access occurs.

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.

finds

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.

mitigates

Access-control rules can limit which files are reachable, reducing exposure to malicious links.

References