CVE-2015-1191 in pigz
Summary
by MITRE
Multiple directory traversal vulnerabilities in pigz 2.3.1 allow remote attackers to write to arbitrary files via a (1) full pathname or (2) .. (dot dot) in an archive.
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Analysis
by VulDB Data Team • 11/30/2024
The vulnerability identified as CVE-2015-1191 represents a critical directory traversal flaw within the pigz compression utility version 2.3.1. This issue affects the decompression functionality of the tool and stems from inadequate input validation when processing archive files. The vulnerability enables remote attackers to manipulate the extraction process and write files to arbitrary locations on the target system. The flaw manifests through two distinct attack vectors: the first involves the use of full pathnames within archive files that bypass normal directory restrictions, while the second leverages the .. (dot dot) traversal sequences commonly found in file paths. Both methods exploit the underlying assumption that archive contents will be extracted to predetermined locations without proper validation of the target file paths.
The technical implementation of this vulnerability resides in the archive extraction logic where pigz fails to sanitize or validate file paths before writing decompressed content to disk. When processing compressed archives, the utility does not properly check whether the destination paths specified in the archive metadata are within the intended extraction directory. This allows attackers to craft malicious archive files containing specially formatted paths that, when decompressed, will overwrite system files or create new files in sensitive locations. The vulnerability is particularly dangerous because it operates at the file system level, potentially allowing attackers to escalate privileges or corrupt critical system components. The flaw can be exploited through various means including web-based file upload interfaces, automated backup systems, or any scenario where pigz processes untrusted archive files.
The operational impact of CVE-2015-1191 extends beyond simple file overwrite capabilities and can lead to significant system compromise. Attackers can leverage this vulnerability to overwrite critical system binaries, configuration files, or even create backdoor access points through the manipulation of system files. The vulnerability affects both local and remote exploitation scenarios, making it particularly dangerous in environments where users can upload or process compressed files from untrusted sources. In enterprise environments, this vulnerability could enable attackers to compromise servers running backup systems, web applications, or any service that utilizes pigz for file decompression. The potential for privilege escalation increases when the decompression process runs with elevated privileges, as the attacker could target system directories or files that require administrative access to modify.
Security mitigations for CVE-2015-1191 should focus on immediate patching of affected pigz installations to version 2.3.2 or later, which contains the necessary fixes for path validation. Organizations should implement strict input validation for all archive processing activities and consider deploying sandboxed environments for decompressing untrusted files. Network segmentation and access controls should limit the ability of untrusted users to interact with systems that process compressed files. Additionally, monitoring systems should be configured to detect unusual file modification patterns that might indicate exploitation attempts. The vulnerability aligns with CWE-22 Directory Traversal and CWE-77 Path Traversal, and maps to ATT&CK techniques involving privilege escalation and persistence through file system manipulation. Organizations should also consider implementing automated vulnerability scanning to identify other potentially affected systems running outdated versions of pigz or similar compression utilities. Regular security audits of file processing components and proper input sanitization practices should be enforced across all software that handles user-supplied archive files.