CVE-2017-1000084 in Jenkins
Summary
by MITRE
Parameterized Trigger Plugin fails to check Item/Build permission: The Parameterized Trigger Plugin did not check the build authentication it was running as and allowed triggering any other project in Jenkins.
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Analysis
by VulDB Data Team • 11/21/2019
The Parameterized Trigger Plugin vulnerability represents a critical access control flaw that undermines fundamental security principles within Jenkins continuous integration environments. This vulnerability specifically affects the plugin's handling of build permissions, creating a scenario where unauthorized users can trigger arbitrary projects within the Jenkins instance. The flaw stems from the plugin's failure to properly validate authentication contexts when executing parameterized builds, allowing attackers to exploit this weakness to escalate their privileges and gain access to restricted project resources. The vulnerability exists at the intersection of authentication and authorization mechanisms, where the plugin assumes that any build trigger operation should be permitted without proper verification of the executing user's credentials and permissions.
The technical implementation of this vulnerability resides in the plugin's insufficient validation of Item/Build permissions during trigger operations. When a build is initiated through the Parameterized Trigger Plugin, the system should verify that the user has appropriate permissions to execute the target project. However, the plugin bypasses this critical verification step, allowing any authenticated user to trigger builds against projects they normally wouldn't have access to. This design flaw creates a privilege escalation vector where attackers can manipulate the plugin to execute builds against sensitive projects, potentially exposing confidential information or disrupting critical workflows. The vulnerability aligns with CWE-284, which addresses improper access control, and demonstrates how inadequate permission checking can lead to unauthorized system access.
The operational impact of this vulnerability extends beyond simple unauthorized access, creating potential risks for organizations that rely on Jenkins for their software development and deployment pipelines. Attackers could leverage this vulnerability to trigger builds against projects containing sensitive configurations, secret keys, or proprietary code repositories. The implications become particularly severe when considering that Jenkins instances often house multiple projects with varying levels of sensitivity and access controls. An attacker could potentially discover and exploit this vulnerability to access projects containing production deployment configurations, database credentials, or other critical system information. This vulnerability also enables denial-of-service attacks by triggering resource-intensive builds against projects that could destabilize the Jenkins instance or consume excessive computing resources.
Mitigation strategies for this vulnerability should focus on immediate plugin updates and enhanced access control measures within Jenkins environments. Organizations must ensure they are running the latest versions of the Parameterized Trigger Plugin where the permission checking mechanism has been properly implemented. Security administrators should also review and strengthen their Jenkins permission configurations, implementing more granular access controls that limit project triggering capabilities based on user roles and responsibilities. The remediation process should include comprehensive auditing of all Jenkins plugins to identify similar permission bypass vulnerabilities, as this flaw demonstrates how seemingly minor authentication checks can create significant security risks. Additionally, implementing network-level restrictions and monitoring for unusual build triggering patterns can help detect exploitation attempts and provide early warning of potential security incidents. This vulnerability serves as a reminder of the critical importance of proper authentication verification in automated systems and aligns with ATT&CK technique T1078 for valid accounts and T1059 for command and scripting interpreter, highlighting how unauthorized access can be achieved through legitimate system interfaces.