CVE-2026-12537: Unauthenticated Remote Code Execution in Gemini CLI CI/CD Workflows

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-24 · updated 2026-07-02
Weakness: CWE-20

Description

Improper Neutralization used in an OS Command in the container launcher in Google Gemini CLI (versions prior to 0.39.1) and run-gemini-cli GitHub Action (versions prior to 0.1.22) on headless CI platforms allows an unprivileged attacker to achieve pre-sandbox host-level code execution a maliciously crafted .gemini/.env file.

Affected products

Google Gemini-Cli: before 0.39.1; 0.40.0-preview2 — fixed in 0.39.1
Google Run-Gemini-Cli: before 0.1.22 — fixed in 0.1.22

How to fix

Upgrade to a fixed version: Google Gemini-Cli 0.39.1; Google Run-Gemini-Cli 0.1.22. Check the vendor advisory for mitigations.

References

https://github.com/google-github-actions/run-gemini-cli/security/advisories/GHSA-wpqr-6v78-jr5g

Get alerted when CVE-2026-12537 or the next vulnerability affects your stack