Arbitrary file truncation via output-path TOCTOU race
Published Apr 22, 2026 · Updated Apr 22, 2026
TOCTOU in the split utility of uutils coreutils allows local users to truncate or overwrite unintended files through output-path swaps. Split validates input and output identity by pathname, then separately opens the output with truncation without verifying the opened file's identity. Exploitation requires write access to a mutable path component during the race window, and the process can damage only files accessible under its privileges.
Summary
What happened
TOCTOU in the split utility of uutils coreutils allows local users to truncate or overwrite unintended files through output-path swaps. Split validates input and output identity by pathname, then separately opens the output with truncation without verifying the opened file's identity. Exploitation requires write access to a mutable path component during the race window, and the process can damage only files accessible under its privileges.
The record
- CVE
- CVE-2026-35374
- Published
- Apr 22, 2026
- Updated
- Apr 22, 2026
- Vendor
- uutils
- Product
- coreutils
- Classifications
- CWE-367
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 22, 2026CVE publishedPublication date reported by the CVE source.
- Apr 22, 2026Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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