Ubuntu USN · USN-8428-1

tmux vulnerability

Published: Mon, 15 Jun 2026 13:03

CVE-2026-11623

Summary

tmux could be made to crash if it received specially crafted input.

Details

It was discovered that tmux incorrectly handled image cleanup, leading to a use-after-free vulnerability. A local attacker could possibly use this issue to cause tmux to crash, resulting in a denial of service.

Recommended actions per Ubuntu release

StackPatch playbook auto-generated per release codename and per affected package.

Ubuntu resolute

tmux→3.6a-2ubuntu0.1apt_upgrade
Standard apt upgrade. Install 3.6a-2ubuntu0.1 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y tmux
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
tmux→3.6a-2ubuntu0.1apt_upgrade
Standard apt upgrade. Install 3.6a-2ubuntu0.1 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y tmux
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Are YOU affected by USN-8428-1?

5-second check on your actual server. Reads /etc/os-release, uname -r, and dpkg-query; matches against the live USN + Debian Security Tracker feeds; tells you whether USN-8428-1 (and any other live CVE) applies. Anonymous, no signup.

curl https://mindsparkstack.com/scan.sh | bash

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