CVE-2020-2249

Vulnerability

Overview

The Jenkins Team Foundation Server Plugin, up to version 5.157.1, stores a webhook secret unencrypted in its global configuration file on the Jenkins controller. This plain-text storage violates best practices for credential handling, exposing sensitive information to anyone with access to the controller's file system. [1][2]

Exploitation

To exploit this vulnerability, an attacker must have access to the Jenkins controller's file system. This access could be achieved through other vulnerabilities or legitimate means, such as low-privileged user access on the operating system. No additional authentication or network position is required beyond file system read permissions. The attacker can then read the configuration file containing the webhook secret. [1][2][3]

Impact

With the exposed webhook secret, an attacker can potentially forge webhook requests or access associated Azure DevOps/TFS resources, depending on the secret's purpose. This could lead to unauthorized actions in connected services, such as triggering builds or manipulating repositories. [1][2][4]

Mitigation

The Jenkins Security Advisory 2020-09-01 notes that this security issue was *not* fixed in a plugin update, as the Team Foundation Server Plugin was reported to have unresolved issues. Users should consider removing or replacing the plugin if possible, or implementing additional access controls to restrict file system access on the Jenkins controller. [2][3]