CVE-2020-27347: tmux stack buffer overflow in function input_csi_dispatch_sgr_colon

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2020-11-06 · updated 2026-06-17
Weakness: CWE-121

Description

In tmux before version 3.1c the function input_csi_dispatch_sgr_colon() in file input.c contained a stack-based buffer-overflow that can be exploited by terminal output.

Affected products

Tmux Project Tmux: from 2.9 through 3.1b

References

https://github.com/tmux/tmux/commit/a868bacb46e3c900530bed47a1c6f85b0fbe701c
https://raw.githubusercontent.com/tmux/tmux/3.1c/CHANGES
https://security.gentoo.org/glsa/202011-10
https://www.openwall.com/lists/oss-security/2020/11/05/3
https://github.com/tmux/tmux/commit/a868bacb46e3c900530bed47a1c6f85b0fbe701c
https://raw.githubusercontent.com/tmux/tmux/3.1c/CHANGES
https://security.gentoo.org/glsa/202011-10
https://www.openwall.com/lists/oss-security/2020/11/05/3

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