Description
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.
Affected products
uutils: coreutils
References5
- github.com/uutils/coreutils/issues/10020 ExploitIssue TrackingVendor Advisory
- github.com/uutils/coreutils/issues/10020 ExploitIssue TrackingVendor Advisory
- www.openwall.com/lists/oss-security/2026/05/04/4
- www.openwall.com/lists/oss-security/2026/05/04/5
- www.openwall.com/lists/oss-security/2026/05/04/6
Metrics
- CVSS 3.1
-
7.0
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 4 · as of 13 November 2026
- CWE
- CWE-367
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