CVE-2026-109429
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.56%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.56% probability · 46th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-436
- Source
- disclosure@vulncheck.com
EPSS moved from 0.6% on 14 October 2026 to 0.6% on 26 October 2026.
References
- https://github.com/mistralai/mistral-vibe/commit/19b5b74faa78d0816b8d4d4c7d7543fc3520678c
- https://github.com/mistralai/mistral-vibe/pull/1084
- https://github.com/mistralai/mistral-vibe/releases/tag/v2.25.4
- https://www.vulncheck.com/advisories/mistral-vibe-bash-permission-bypass-via-var-p-prompt-transform
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.