CVE-2026-2244 is a vulnerability identified in Google Cloud's Vertex AI Workbench affecting versions deployed between July 21, 2025, and January 30, 2026. The flaw arises from a built-in startup script that can be abused by an attacker to exfiltrate valid Google Cloud access tokens belonging to other users. These tokens grant access to Google Cloud resources, so their theft can lead to unauthorized actions within the cloud environment. The vulnerability is classified under CWE-200, indicating exposure of sensitive information to unauthorized actors. Exploitation requires low privileges (PR:L) and user interaction (UI:A), but no authentication (AT:N) is needed to initiate the attack, making it relatively easy to exploit in environments where an attacker can trigger the startup script. The vulnerability has a high CVSS 4.0 score of 8.4, reflecting the critical confidentiality impact (VC:H) and the broad scope of affected components (SI:H, SA:H). Google patched this vulnerability in all instances deployed after January 30, 2026, and no user action is required for patched versions. No known exploits have been reported in the wild, but the potential for token theft poses a significant risk to cloud security.

The primary impact of CVE-2026-2244 is the unauthorized disclosure of Google Cloud access tokens, which can lead to significant confidentiality breaches. Attackers who successfully exploit this vulnerability can impersonate legitimate users and gain unauthorized access to cloud resources, potentially leading to data theft, service disruption, or further lateral movement within the cloud environment. This can compromise the integrity and availability of cloud workloads managed via Vertex AI Workbench. Organizations relying on Vertex AI Workbench for AI development and deployment may face operational disruptions and reputational damage if attackers leverage stolen tokens to manipulate or exfiltrate sensitive data. The ease of exploitation combined with the high privileges granted by stolen tokens amplifies the threat, especially in multi-tenant or collaborative cloud environments.

To mitigate CVE-2026-2244, organizations should ensure that all Vertex AI Workbench instances are updated to versions deployed after January 30, 2026, where the vulnerability has been patched. Administrators should audit existing instances to confirm the absence of vulnerable startup scripts and revoke any potentially compromised access tokens issued during the vulnerable period. Implement strict monitoring and alerting for unusual token usage or access patterns within Google Cloud environments. Employ the principle of least privilege for service accounts and users to limit the impact of token compromise. Additionally, consider enabling token expiration and rotation policies to reduce the window of opportunity for attackers. Regularly review and harden startup scripts and automation workflows to prevent unauthorized code execution or token exposure. Finally, educate users about the risks of interacting with untrusted scripts or environments that could trigger this vulnerability.