CVE-2015-5273 in Automatic Bug Reporting Tool
Summary
by MITRE
The abrt-action-install-debuginfo-to-abrt-cache help program in Automatic Bug Reporting Tool (ABRT) before 2.7.1 allows local users to write to arbitrary files via a symlink attack on unpacked.cpio in a pre-created directory with a predictable name in /var/tmp.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 12/25/2024
The CVE-2015-5273 vulnerability resides within the Automatic Bug Reporting Tool (ABRT) ecosystem, specifically targeting the abrt-action-install-debuginfo-to-abrt-cache help program. This flaw represents a classic symlink attack vector that exploits predictable temporary file creation patterns within the /var/tmp directory structure. The vulnerability affects ABRT versions prior to 2.7.1 and demonstrates how improper temporary file handling can lead to privilege escalation and arbitrary file write capabilities. The issue stems from the program's failure to properly validate file paths when creating temporary directories with predictable naming conventions, creating opportunities for local attackers to manipulate the file system through symbolic link manipulation.
The technical exploitation mechanism involves the attacker creating a malicious symbolic link that points to a target file they wish to modify, then triggering the vulnerable program to create a temporary directory with a predictable name in /var/tmp. When the program processes the unpacked.cpio file, it follows the symbolic link and writes data to the attacker-controlled target file rather than the intended temporary location. This represents a direct violation of the principle of least privilege and demonstrates poor input validation practices in temporary file creation. The vulnerability aligns with CWE-367, which addresses time-of-check to time-of-use (TOCTOU) race conditions, and more specifically with CWE-22, which covers improper limitation of a pathname to a restricted directory. The attack requires local system access but can potentially escalate privileges if the target file is owned by a more privileged user or system process.
The operational impact of this vulnerability extends beyond simple file modification, as it can be leveraged to compromise system integrity and potentially enable further attacks within the ABRT environment. Attackers could use this vector to overwrite critical system files, modify configuration data, or inject malicious code into the debugging infrastructure. The vulnerability is particularly concerning in environments where ABRT is used for automated bug reporting and system diagnostics, as it could allow attackers to corrupt the debugging process or manipulate crash reports. This type of attack can also facilitate persistence mechanisms if the attacker targets files within the ABRT cache or configuration directories. The vulnerability's impact is amplified by the fact that ABRT is commonly installed on production systems where it may have elevated privileges during debugging operations.
Mitigation strategies for CVE-2015-5273 should focus on implementing proper temporary file handling practices and addressing the root cause of the symlink attack. System administrators should immediately upgrade to ABRT version 2.7.1 or later, which contains the necessary patches to prevent predictable temporary directory creation. The fix typically involves implementing proper file path validation, using secure temporary directory creation methods such as mkdtemp(), and ensuring that symbolic link resolution is properly handled during file operations. Organizations should also consider implementing additional security controls such as restricting write permissions on the /var/tmp directory, monitoring for suspicious symbolic link creation patterns, and applying the principle of least privilege to ABRT processes. This vulnerability demonstrates the importance of secure coding practices and proper temporary file management, aligning with ATT&CK technique T1059.007 for execution through command-line interfaces and T1548.003 for elevation of privileges through local exploitation. Regular security audits and vulnerability assessments should include checks for similar patterns in other system tools to prevent analogous issues from emerging in the broader software ecosystem.