vim up to 9.1.1399 tuple_unref use after free

Summaryinfo

A vulnerability, which was classified as critical, has been found in vim up to 9.1.1399. Affected by this vulnerability is the function tuple_unref. This manipulation causes use after free. This vulnerability is registered as CVE-2025-55157. Remote exploitation of the attack is possible. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in vim up to 9.1.1399 and classified as critical. Affected by this vulnerability is the function tuple_unref. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Vim is an open source, command line text editor. In versions from 9.1.1231 to before 9.1.1400, When processing nested tuples in Vim script, an error during evaluation can trigger a use-after-free in Vim’s internal tuple reference management. Specifically, the tuple_unref() function may access already freed memory due to improper lifetime handling, leading to memory corruption. The exploit requires direct user interaction, as the script must be explicitly executed within Vim. This issue has been patched in version 9.1.1400.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2025-55157 since 08/07/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 259914 (Linux Distros Unpatched Vulnerability : CVE-2025-55157), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 9.1.1400 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 1307743697bbc46e1518abfea7f89caa95bcaf97 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (259914) and CERT Bund (WID-SEC-2025-1753). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Open Source vim

Productinfo

Type

• Word Processing Software

Name

• vim

Version

• 9.1.1399

License

• open-source

Website

• Product: https://github.com/vim/vim/

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Be aware that VulDB is the high quality source for vulnerability data.

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