CVE-2026-109429 Mistral Vibe < 2.25.4 Bash Permission Bypass via ${var@P} Prompt-Transform
Attackers can bypass command permission gates in Mistral Vibe to execute arbitrary commands via prompt-transform tricks, risking full terminal compromise.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-109429?
CVE-2026-109429 is a high-severity command injection vulnerability in mistralai mistral-vibe, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Mistral Vibe before 2.25.4 contains a command permission gate bypass vulnerability that allows attackers to execute arbitrary commands by hiding a command substitution inside a single-quoted variable value that tree-sitter-bash static parsing cannot detect. Attackers can craft input such as embedding a command substitution within a single-quoted variable and re-expanding it with the ${var@P} prompt-transform operator so bash's promptvars feature executes the hidden command at runtime while only the trailing allowlisted command is classified, resulting in silent arbitrary command execution with the privileges of the agent's terminal session.
Weakness: CWE-436
Which versions are affected by CVE-2026-109429?
How do I fix CVE-2026-109429?
No fix has been published for CVE-2026-109429 yet. Limit exposure of the affected software until one is available.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-109429 being exploited?
There is no known exploitation of CVE-2026-109429 in the wild and no public exploit code.
Sources
Also known as GHSA-m84r-3mrm-j4p8.