# CVE-2026-35357: uutils coreutils has a Time-of-check Time-of-use (TOCTOU) Race Condition

Source: https://junglewise.ai/threats/cve-2026-35357-uutils-coreutils-has-a-time-of-check-time-of-use-toctou-race  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-22  
License: CC BY 4.0 with a link back

CVE-2026-35357 · Severity: medium · CVSS 4.7 · Published 2026-04-22

The cp utility in uutils coreutils is vulnerable to an information disclosure race condition. Destination files are initially created with umask-derived permissions (e.g., 0644) before being restricted to their final mode (e.g., 0600) later in the process. A local attacker can race to open the file during this window; once obtained, the file descriptor remains valid and readable even after the permissions are tightened, exposing sensitive or private file contents.

Technologies: [coreutils (crates.io)](https://junglewise.ai/threats/technologies/crates-io-coreutils), [Uutils Coreutils](https://junglewise.ai/threats/technologies/uutils-coreutils). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io), [Uutils](https://junglewise.ai/threats/vendors/uutils).

## Quick answers

**Is CVE-2026-35357 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-35357 being exploited in the wild.

**How severe is CVE-2026-35357?** Medium severity, with a CVSS score of 4.7, published 22 April 2026.

**Which products and versions are affected?** coreutils (crates.io) SEMVER:introduced=0,last_affected=0.8.0.

**Is there a fix for CVE-2026-35357?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**Am I affected by CVE-2026-35357?** Check whether you run coreutils (crates.io) or Uutils Coreutils at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- coreutils (crates.io) SEMVER:introduced=0,last_affected=0.8.0
- Uutils Coreutils

## Identifiers

- CVE-2026-35357
- GHSA-2m8x-mvfx-gwgj

## Related threats

- [uutils coreutils Incorrect Provision of Specified Functionality in cut](https://junglewise.ai/threats/cve-2026-35381-uutils-coreutils-incorrect-provision-of-specified-functionality)
- [uutils coreutils has an Improper Input Validation Issue in its cut Utility](https://junglewise.ai/threats/cve-2026-35380-uutils-coreutils-has-an-improper-input-validation-issue-in-its)
- [A logic error in the tr utility of uutils coreutils causes the program to incorrectly define the [:graph:] and [:print:] character classes.](https://junglewise.ai/threats/cve-2026-35379-uutils-coreutils-has-an-incorrect-provision-of-specified)
- [uutils coreutils has an Incorrect Short Circuit Evaluation Issue](https://junglewise.ai/threats/cve-2026-35378-uutils-coreutils-has-an-incorrect-short-circuit-evaluation-issue)
- [uutils coreutils has an Improper Input Validation Issue in its env Utility](https://junglewise.ai/threats/cve-2026-35377-uutils-coreutils-has-an-improper-input-validation-issue-in-its)