CVE-2020-13265 in Community Edition
Summary
by MITRE
User email verification bypass in GitLab CE/EE 12.5 and later through 13.0.1 allows user to bypass email verification
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Analysis
by VulDB Data Team • 10/26/2020
The vulnerability CVE-2020-13265 represents a critical security flaw in GitLab Community Edition and Enterprise Edition versions ranging from 12.5 through 13.0.1 that allows unauthorized users to bypass email verification requirements during account registration. This issue stems from a design flaw in the email verification mechanism that fails to properly validate user authentication status before granting access to restricted functionalities. The flaw specifically affects the user registration and account activation workflows where the system should enforce mandatory email verification before permitting full user privileges. This vulnerability enables attackers to create accounts without completing the required email confirmation process, effectively undermining the security controls designed to verify user identities and prevent spam or malicious account creation.
The technical implementation of this vulnerability resides in the insufficient validation logic within GitLab's authentication and authorization modules. When users register for accounts, the system should enforce a strict verification workflow that requires email confirmation before granting access to core platform features. However, the flaw allows users to bypass this verification step through manipulation of the registration process or by exploiting timing gaps in the verification workflow. The vulnerability can be exploited through various attack vectors including automated account creation scripts that leverage the system's failure to properly validate email confirmation status before granting user privileges. This issue falls under the CWE-613 weakness category, which addresses insufficient validation of security tokens or authentication states, and aligns with ATT&CK technique T1078.004 for valid accounts and T1566.001 for spearphishing with a link, as attackers can create verified accounts without proper email confirmation.
The operational impact of this vulnerability extends beyond simple account creation bypasses as it creates potential entry points for malicious actors to establish persistent access to GitLab instances. Attackers can leverage this flaw to create multiple accounts rapidly without email verification, enabling them to perform actions such as repository creation, code commits, and access to sensitive project information. The vulnerability also poses risks to GitLab's integrity and access control mechanisms, as it allows unauthorized users to bypass the platform's user management controls. Organizations using affected GitLab versions may experience unauthorized access to repositories, potential data exposure through code commits from unverified accounts, and increased risk of spam or abuse within their development environments. The impact is particularly severe in enterprise environments where GitLab serves as a central code repository and collaboration platform, as unauthorized access can compromise sensitive source code and development workflows.
Mitigation strategies for CVE-2020-13265 require immediate patching of affected GitLab installations to version 13.1 or later where the vulnerability has been addressed. Organizations should also implement additional monitoring controls to detect unusual account creation patterns and verify email confirmation status through automated systems. Security teams should review existing access controls and user management policies to ensure that newly created accounts are properly validated before granting full privileges. The fix implemented by GitLab developers addresses the core validation logic in the email verification workflow, ensuring that users cannot access platform features without completing the required email confirmation process. Organizations should also consider implementing rate limiting and automated account verification monitoring as additional defensive measures. Compliance with security standards such as NIST SP 800-53 and ISO 27001 requires proper account validation and access control mechanisms, making this vulnerability particularly concerning for regulated environments. Regular security assessments and vulnerability scanning should be conducted to identify similar issues in other components of the GitLab platform or related systems.