Vulnerability · Published Apr 22, 2026 · Assigned by canonical
CVE-2026-35378uutils coreutils expr Local Denial of Service via Eager Evaluation of Parenthesized Subexpressions
Low 3.3
In plain English
A low-severity security flaw in coreutils from Uutils. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
A logic error in the expr utility of uutils coreutils causes the program to evaluate parenthesized subexpressions during the parsing phase rather than at the execution phase. This implementation flaw prevents the utility from performing proper short-circuiting for logical OR (|) and AND (&) operations. As a result, arithmetic errors (such as division by zero) occurring within "dead" branches, branches that should be ignored due to short-circuiting, are raised as fatal errors. This divergence from GNU expr behavior can cause guarded expressions within shell scripts to fail with hard errors instead of returning expected boolean results, leading to premature script termination and breaking GNU-compatible shell control flow.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | rust-coreutils | no fix listed | DEBIAN-CVE-2026-35378 |
| Debian:13 | rust-coreutils | no fix listed | DEBIAN-CVE-2026-35378 |
| Debian:14 | rust-coreutils | 0.8.0-1 | DEBIAN-CVE-2026-35378 |
| Ubuntu:24.04:LTS | rust-coreutils | no fix listed | UBUNTU-CVE-2026-35378 |
| Ubuntu:25.10 | rust-coreutils | no fix listed | UBUNTU-CVE-2026-35378 |
Affected products (as reported)
Weakness: CWE-768 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
References
- https://github.com/uutils/coreutils/pull/11395 issue-tracking, patch
- https://github.com/uutils/coreutils/releases/tag/0.8.0 vendor-advisory