Uutils coreutils up to 0.5.x Install Utility toctou

Summaryinfo

A vulnerability has been found in Uutils coreutils up to 0.5.x and classified as problematic. This issue affects some unknown processing of the component Install Utility. The manipulation leads to toctou. This vulnerability is listed as CVE-2026-35355. The attack must be carried out locally. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Uutils coreutils up to 0.5.x and classified as problematic. This issue affects an unknown part of the component Install Utility. The manipulation with an unknown input leads to a toctou vulnerability. Using CWE to declare the problem leads to CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. Impacted is integrity, and availability. The summary by CVE is:

The install utility in uutils coreutils is vulnerable to a Time-of-Check to Time-of-Use (TOCTOU) race condition during file installation. The implementation unlinks an existing destination file and then recreates it using a path-based operation without the O_EXCL flag. A local attacker can exploit the window between the unlink and the subsequent creation to swap the path with a symbolic link, allowing them to redirect privileged writes to overwrite arbitrary system files.

The weakness was presented by Zellic. The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-35355 since 04/02/2026. The exploitation is known to be difficult. An attack has to be approached locally. Neither technical details nor an exploit are publicly available.

Upgrading to version 0.6.0 eliminates this vulnerability.

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Productinfo

Vendor

• Uutils

Name

• coreutils

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5

Website

• Product: https://github.com/uutils/coreutils/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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