Uutils coreutils tail Utility toctou

Summaryinfo

A vulnerability was found in Uutils coreutils. It has been classified as problematic. This affects an unknown function of the component tail Utility. This manipulation causes toctou. This vulnerability appears as CVE-2026-35345. The attack requires local access. There is no available exploit.

Detailsinfo

A vulnerability classified as problematic was found in Uutils coreutils (unknown version). Affected by this vulnerability is an unknown code block of the component tail Utility. The manipulation with an unknown input leads to a toctou vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A vulnerability in the tail utility of uutils coreutils allows for the exfiltration of sensitive file contents when using the --follow=name option. Unlike GNU tail, the uutils implementation continues to monitor a path after it has been replaced by a symbolic link, subsequently outputting the contents of the link's target. In environments where a privileged user (e.g., root) monitors a log directory, a local attacker with write access to that directory can replace a log file with a symlink to a sensitive system file (such as /etc/shadow), causing tail to disclose the contents of the sensitive file.

The weakness was presented by Zellic. The advisory is shared at github.com. This vulnerability is known as CVE-2026-35345 since 04/02/2026. The exploitation appears to be difficult. An attack has to be approached locally. Neither technical details nor an exploit are publicly available.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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

Productinfo

Vendor

• Uutils

Name

• coreutils

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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