CVE-2010-2449 in Gource
Summary
by MITRE
Gource through 0.26 logs to a predictable file name (/tmp/gource-$UID.tmp), enabling attackers to overwrite an arbitrary file via a symlink attack.
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Analysis
by VulDB Data Team • 02/05/2024
The vulnerability identified as CVE-2010-2449 affects Gource version 0.26 and earlier, representing a critical security flaw that stems from improper temporary file handling within the application. This issue manifests when Gource generates log files using a predictable naming convention that includes the user identifier, specifically /tmp/gource-$UID.tmp. The predictable nature of this file path creates a significant attack surface that malicious actors can exploit through symlink manipulation techniques.
The technical flaw resides in the application's failure to implement secure temporary file creation practices, which directly correlates to CWE-377 - Insecure Temporary File and CWE-378 - Creation of Temporary File With Insecure Permissions. When Gource runs with elevated privileges or as a regular user, it creates temporary files in the /tmp directory without proper security measures to prevent symlink attacks. Attackers can create symbolic links with the predictable names in advance of Gource execution, effectively redirecting the application's write operations to arbitrary locations on the filesystem.
This vulnerability enables attackers to perform arbitrary file overwrite operations, which can have severe operational consequences depending on the execution context and target system. When Gource runs with elevated privileges, an attacker could potentially overwrite critical system files, configuration files, or even executables, leading to privilege escalation or system compromise. The impact extends beyond simple file overwrite scenarios, as the attacker could also redirect logs to sensitive locations such as authentication files, system configuration directories, or other critical resources. This represents a classic case of a symlink-based attack that aligns with techniques documented in the ATT&CK framework under T1059 - Command and Scripting Interpreter and T1548 - Abuse of Functionality.
The operational impact of this vulnerability is substantial, particularly in multi-user environments or systems where Gource is executed with elevated privileges. Organizations using Gource for software development visualization or version control tracking may unknowingly expose themselves to persistent attack vectors that could be exploited by adversaries with minimal privileges to gain deeper system access. The vulnerability affects any system where the application executes with sufficient privileges to create or modify files in the /tmp directory, making it particularly concerning for shared hosting environments, containerized deployments, or systems with multiple users.
Mitigation strategies for CVE-2010-2449 should focus on implementing secure temporary file creation practices that align with industry standards and best practices. Organizations should ensure that Gource is updated to version 0.27 or later, where the developers have addressed the issue by implementing proper temporary file handling mechanisms. Additionally, system administrators should consider running Gource with reduced privileges when possible, and implement proper file system permissions to limit the impact of potential symlink attacks. The use of secure temporary file creation functions such as mkstemp or mkdtemp should be enforced, and the application should verify that temporary files are created with appropriate permissions and ownership. Network segmentation and monitoring for suspicious file creation patterns in the /tmp directory can provide additional layers of defense against exploitation attempts. Organizations should also consider implementing automated patch management processes to ensure timely updates to security-critical applications and libraries that may be vulnerable to similar symlink-based attacks.