Vulnerability · Published Sep 11, 2026 · Assigned by HiddenLayer

CVE-2026-87984

Critical 9.3

In plain English

A critical-severity path traversal in mistral-vibe from mistralai. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities).

Severity (CVSS 4.0)9.3Critical

Exploit odds (30 days)0.5%top 57.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

An arbitrary file write vulnerability in Mistral Vibe, introduced in version 1.3.4, allows an attacker to create or overwrite files outside the active workspace without user approval. Shell redirection destinations are omitted from permission checks, enabling otherwise allowlisted commands to write to arbitrary paths accessible to the Vibe process.

Affected products (as reported)

Vendor	Product	Versions
mistralai	mistral-vibe	1.3.4 – through *

Weakness: CWE-22 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References

https://www.hiddenlayer.com/sai-security-advisory/2026-09-mistral-vibe2