Description
The comm utility in uutils coreutils incorrectly consumes data from non-regular file inputs before performing comparison operations. The are_files_identical function opens and reads from both input paths to compare content without first verifying if the paths refer to regular files. If an input path is a FIFO or a pipe, this pre-read operation drains the stream, leading to silent data loss before the actual comparison logic is executed. Additionally, the utility may hang indefinitely if it attempts to pre-read from infinite streams like /dev/zero.
Affected products
uutils: coreutils
References3
- github.com/uutils/coreutils/pull/9545 Issue TrackingPatch
- github.com/uutils/coreutils/pull/9545 Issue TrackingPatch
- github.com/uutils/coreutils/releases/tag/0.6.0 Release Notes
Metrics
- CVSS 3.1
-
4.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L - EPSS — exploit probability
- 0% percentile: 3 · as of 13 November 2026
- CWE
- CWE-20
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