Gemini CLI Breach: Critical Vulnerability Enables Code Execution

Executive Summary

In June 2025, a critical security vulnerability was discovered in Google’s Gemini CLI, a newly launched command-line interface designed to streamline interactions with Gemini AI. The breach was first detected on June 27, just two days post-release, allowing attackers to execute malicious code on developers’ systems. This significant oversight raised serious concerns within the cybersecurity community, as it exposed sensitive data and credentials utilized by developers leveraging the tool. The rapid adoption of Gemini CLI among developers meant that the scale of this breach was substantial, potentially impacting countless systems and leading to unauthorized access and data exfiltration, demonstrating a pressing need for robust security measures in software development tools.

 Read the full breach analysis from NHI Mgmt Group here

Key Details

Breach Timeline

• June 25, 2025: Gemini CLI officially launched.
• June 27, 2025: Security researchers at Tracebit identify the vulnerability.
• July 2025: Reports emerge detailing the extent of the breach and its potential impact.

Data Compromised

• Sensitive developer credentials, including API keys and access tokens, were at risk.
• Potential exfiltration of proprietary code and personal data from developers’ systems.

Impact Assessment

• The breach could affect thousands of developers who adopted the Gemini CLI tool shortly after its release.
• Unauthorized access may lead to financial losses and damage to company reputations.

Company Response

• Google initiated an urgent investigation and issued a patch to fix the vulnerability.
• Developers were advised to update their systems immediately to mitigate the risks.

Security Implications

• This incident underscores the importance of rigorous security testing before deploying new software tools.
• It highlights the need for ongoing security training for developers using AI-assisted coding tools.

 If you want to learn more about how to secure NHIs including AI Agents, check our NHI Foundational Training Course.