CVE-2017-1000242 in Git Client Plugin
Summary
by MITRE
Jenkins Git Client Plugin 2.4.2 and earlier creates temporary file with insecure permissions resulting in information disclosure
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Analysis
by VulDB Data Team • 01/21/2021
The vulnerability identified as CVE-2017-1000242 affects the Jenkins Git Client Plugin version 2.4.2 and earlier, representing a critical security flaw that undermines the integrity of temporary file handling mechanisms within the Jenkins continuous integration environment. This issue stems from the plugin's failure to properly secure temporary files during git operations, creating a pathway for unauthorized information disclosure that can compromise sensitive data within the build environment.
The technical flaw manifests through insecure temporary file creation practices that violate fundamental security principles governing file system permissions and access controls. When the Jenkins Git Client Plugin performs git operations, it generates temporary files that are created with overly permissive access controls, typically allowing world-readable or world-writable permissions. This insecure default configuration enables local users or processes running with equivalent privileges to access or modify these temporary files, potentially exposing sensitive information such as credentials, build artifacts, or other confidential data that may be stored within these temporary locations during git operations.
The operational impact of this vulnerability extends beyond simple information disclosure to encompass potential privilege escalation and data compromise within Jenkins environments. Attackers who can leverage this flaw may gain access to repository credentials, API tokens, or other authentication materials stored in temporary files, enabling them to perform unauthorized git operations or access protected repositories. The vulnerability particularly affects environments where Jenkins runs with elevated privileges or where multiple users share the same system, as the insecure temporary file permissions create a persistent attack surface that can be exploited over time. This issue also aligns with CWE-377, which addresses insecure temporary files, and represents a direct violation of the principle of least privilege in file system security management.
Mitigation strategies for CVE-2017-1000242 require immediate plugin version updates to 2.4.3 or later, which contain the necessary fixes to properly secure temporary file creation and implement appropriate access controls. Organizations should also implement comprehensive monitoring of temporary file creation and access patterns within Jenkins environments, ensuring that any unauthorized access attempts are detected and investigated. Additional protective measures include restricting Jenkins process privileges, implementing proper file system permissions, and conducting regular security assessments of build environments to identify and remediate similar insecure practices. The vulnerability demonstrates the critical importance of secure temporary file handling practices and aligns with ATT&CK technique T1059.001 for executing malicious code through compromised build systems, highlighting the need for comprehensive security controls throughout the software development lifecycle.