CVE-2026-11623: tmux image.c image_free use after free

Severity: medium (CVSS 4.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-09 · updated 2026-07-23
Weakness: CWE-119

Description

A security vulnerability has been detected in tmux up to 3.6a. Affected is the function image_free of the file image.c. Such manipulation leads to use after free. Local access is required to approach this attack. This attack is characterized by high complexity. The exploitability is told to be difficult. The exploit has been disclosed publicly and may be used. Upgrading to version 3.7-rc is able to address this issue. The name of the patch is fc6d94a9f8a593bd8b7031650802084385d4ee03. The affected component should be upgraded.

Affected products

tmux: 3.6a

References

https://gist.github.com/XlabAITeam/f0d9952595f795129a3258ba73bbc3cb
https://github.com/tmux/tmux/
https://github.com/tmux/tmux/commit/fc6d94a9f8a593bd8b7031650802084385d4ee03
https://github.com/tmux/tmux/releases/tag/3.7-rc
https://vuldb.com/cve/CVE-2026-11623
https://vuldb.com/submit/835623
https://vuldb.com/vuln/369303
https://vuldb.com/vuln/369303/cti

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