CVE-2026-35352 PUBLISHED

uutils coreutils mkfifo Privilege Escalation via TOCTOU Race Condition

Assigner: canonical
Reserved: 02.04.2026 Published: 22.04.2026 Updated: 22.04.2026

A Time-of-Check to Time-of-Use (TOCTOU) race condition exists in the mkfifo utility of uutils coreutils. The utility creates a FIFO and then performs a path-based chmod to set permissions. A local attacker with write access to the parent directory can swap the newly created FIFO for a symbolic link between these two operations. This redirects the chmod call to an arbitrary file, potentially enabling privilege escalation if the utility is run with elevated privileges.

Metrics

CVSS Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 7

Product Status

Vendor Uutils
Product coreutils
Versions Default: affected

Credits

  • Zellic finder

References

Problem Types

  • CWE-367: Time-of-Check Time-of-Use (TOCTOU) Race Condition CWE

Impacts

  • CAPEC-29: Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions