CVE-2020-2299 in Active Directory Plugin
Summary
by MITRE • 11/04/2020
Jenkins Active Directory Plugin 2.19 and earlier allows attackers to log in as any user if a magic constant is used as the password.
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Analysis
by VulDB Data Team • 12/02/2020
The vulnerability identified as CVE-2020-2299 affects the Jenkins Active Directory Plugin version 2.19 and earlier, representing a critical authentication bypass flaw that undermines the security posture of Jenkins environments relying on Active Directory integration. This issue stems from improper validation of authentication credentials within the plugin's implementation, creating a pathway for unauthorized access that bypasses normal authentication mechanisms. The vulnerability specifically targets the password validation process where certain predetermined values can be used to authenticate as any user within the Active Directory domain, effectively rendering user authentication controls ineffective.
The technical flaw manifests through the use of a magic constant as a password value that allows attackers to bypass the normal authentication flow entirely. This magic constant serves as a hardcoded value that the plugin accepts without proper validation, enabling attackers to authenticate with elevated privileges regardless of the actual password provided. The vulnerability exists in the plugin's credential handling logic where it fails to properly validate the password against the expected authentication mechanisms, instead accepting the magic constant as a valid authentication token. This flaw operates at the authentication layer and demonstrates a classic case of insecure authentication implementation that violates fundamental security principles.
The operational impact of this vulnerability is severe and far-reaching for organizations using Jenkins with Active Directory integration. Attackers can exploit this vulnerability to gain unauthorized access to Jenkins instances with full administrative privileges, potentially leading to complete system compromise. The ability to log in as any user means that attackers can impersonate legitimate users, access restricted projects and build configurations, and potentially escalate their privileges to gain control over the entire Jenkins infrastructure. This vulnerability directly impacts the integrity and confidentiality of CI/CD pipelines, allowing attackers to modify build scripts, access sensitive source code, and manipulate the software development lifecycle.
Organizations should immediately update their Jenkins Active Directory Plugin to version 2.20 or later to remediate this vulnerability, as the patch addresses the authentication bypass issue by implementing proper password validation mechanisms. Additionally, administrators should conduct thorough security audits of their Jenkins environments to identify any potential exploitation attempts and implement network-level controls to restrict access to Jenkins instances. The vulnerability aligns with CWE-287, which addresses improper authentication, and maps to ATT&CK technique T1078.002 for valid accounts, as attackers can leverage this flaw to obtain legitimate user credentials through unauthorized means. Security monitoring should be enhanced to detect unusual authentication patterns and unauthorized access attempts, while access controls should be reviewed to ensure that only authorized personnel can access the Jenkins administration interface and its associated functionality.