Description
The comm utility in uutils coreutils silently corrupts data by performing lossy UTF-8 conversion on all output lines. The implementation uses String::from_utf8_lossy(), which replaces invalid UTF-8 byte sequences with the Unicode replacement character (U+FFFD). This behavior differs from GNU comm, which processes raw bytes and preserves the original input. This results in corrupted output when the utility is used to compare binary files or files using non-UTF-8 legacy encodings.
Affected products
uutils: coreutils
References4
- github.com/uutils/coreutils/issues/10192 ExploitIssue TrackingVendor Advisory
- github.com/uutils/coreutils/issues/10192 ExploitIssue TrackingVendor Advisory
- github.com/uutils/coreutils/pull/10206 Issue TrackingPatch
- github.com/uutils/coreutils/releases/tag/0.6.0 Release Notes
Metrics
- CVSS 3.1
-
3.3
LOW
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 7 · as of 13 November 2026
- CWE
- CWE-176
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