CVE-2026-12537: CWE-20 Improper Input Validation in Google Cloud Gemini CLI
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.
AI Analysis
Technical Summary
The vulnerability CVE-2026-12537 in Google Cloud Gemini CLI and run-gemini-cli GitHub Action arises from improper neutralization of OS commands in the container launcher component. This allows an attacker who can supply a crafted .gemini/.env file to execute code on the host before sandboxing occurs, effectively escalating privileges on headless continuous integration platforms. The issue affects Gemini CLI versions prior to 0.39.1 and run-gemini-cli GitHub Action versions prior to 0.1.22. The vulnerability is rated critical with a CVSS 4.0 score of 10, indicating network exploitable, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The product is a cloud service, and remediation is managed by Google Cloud.
Potential Impact
An unprivileged attacker can achieve host-level code execution before sandboxing on headless CI platforms by exploiting improper input validation in the Gemini CLI container launcher. This can lead to full compromise of the host environment, affecting confidentiality, integrity, and availability of the system running the vulnerable versions.
Mitigation Recommendations
A patch is available for this vulnerability. Since Gemini CLI is a cloud-hosted service, Google Cloud manages remediation server-side. Users should verify with the vendor advisory for confirmation of patch deployment and ensure they are using Gemini CLI version 0.39.1 or later and run-gemini-cli GitHub Action version 0.1.22 or later to avoid exposure.
CVE-2026-12537: CWE-20 Improper Input Validation in Google Cloud Gemini CLI
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.
CVSS v4.0
Score 10.0critical
Affected software
pkg:github/google-github-actions/run-gemini-clipkg:github/google-cloud/gemini-cliRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-12537 in Google Cloud Gemini CLI and run-gemini-cli GitHub Action arises from improper neutralization of OS commands in the container launcher component. This allows an attacker who can supply a crafted .gemini/.env file to execute code on the host before sandboxing occurs, effectively escalating privileges on headless continuous integration platforms. The issue affects Gemini CLI versions prior to 0.39.1 and run-gemini-cli GitHub Action versions prior to 0.1.22. The vulnerability is rated critical with a CVSS 4.0 score of 10, indicating network exploitable, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The product is a cloud service, and remediation is managed by Google Cloud.
Potential Impact
An unprivileged attacker can achieve host-level code execution before sandboxing on headless CI platforms by exploiting improper input validation in the Gemini CLI container launcher. This can lead to full compromise of the host environment, affecting confidentiality, integrity, and availability of the system running the vulnerable versions.
Mitigation Recommendations
A patch is available for this vulnerability. Since Gemini CLI is a cloud-hosted service, Google Cloud manages remediation server-side. Users should verify with the vendor advisory for confirmation of patch deployment and ensure they are using Gemini CLI version 0.39.1 or later and run-gemini-cli GitHub Action version 0.1.22 or later to avoid exposure.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GoogleCloud
- Date Reserved
- 2026-06-17T15:08:00.562Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
- Is Cloud Service
- true
Threat ID: 6a3be194eed863c81eeb9649
Added to database: 06/24/2026, 13:54:28 UTC
Last enriched: 07/02/2026, 23:02:29 UTC
Last updated: 08/08/2026, 12:41:08 UTC
Views: 234
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