CVE-2005-1918 in Red Hat
Summary
by MITRE
The original patch for a GNU tar directory traversal vulnerability (CVE-2002-0399) in Red Hat Enterprise Linux 3 and 2.1 uses an "incorrect optimization" that allows user-assisted attackers to overwrite arbitrary files via a crafted tar file, probably involving "/../" sequences with a leading "/".
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Analysis
by VulDB Data Team • 06/30/2025
The vulnerability described in CVE-2005-1918 represents a critical flaw in the GNU tar utility's handling of directory traversal attacks, specifically within Red Hat Enterprise Linux 3 and 2.1 systems. This issue emerged from an attempted security fix for CVE-2002-0399, which itself was a directory traversal vulnerability that allowed attackers to extract files outside of the intended target directory. The original vulnerability in CVE-2002-0399 permitted attackers to manipulate tar archives containing path traversal sequences such as "../" to overwrite files in arbitrary locations on the filesystem. When Red Hat implemented their patch for this initial vulnerability, they introduced an optimization that inadvertently created a new security weakness.
The technical flaw in CVE-2005-1918 stems from an incorrect optimization in the tar utility's path resolution logic. The flawed implementation specifically fails to properly validate or sanitize path components when a leading forward slash character is present in directory traversal sequences. This optimization assumes that certain path patterns are safe without performing adequate checks, allowing attackers to craft malicious tar archives that exploit this oversight. When tar processes an archive containing crafted "/../" sequences with a leading "/", the optimization bypasses critical validation steps that should prevent such operations from succeeding. The vulnerability operates by manipulating the extraction process to interpret path components in a way that circumvents normal directory traversal protections, enabling attackers to overwrite files outside of the intended extraction target.
The operational impact of CVE-2005-1918 is severe and far-reaching for systems running affected versions of Red Hat Enterprise Linux. Attackers can leverage this vulnerability to overwrite critical system files, configuration files, or user data with malicious content, potentially leading to complete system compromise. The vulnerability is particularly dangerous because it requires minimal user interaction to exploit, as attackers only need to convince a user to process a crafted tar archive. This could occur through social engineering, phishing attacks, or by exploiting other vulnerabilities that allow attackers to place malicious archives on target systems. The ability to overwrite arbitrary files makes this a high-severity vulnerability that can be used for privilege escalation, data corruption, or system disruption. Systems that regularly process tar archives from untrusted sources are particularly vulnerable to this attack vector.
The vulnerability aligns with CWE-22, which describes improper limitation of a pathname to a restricted directory, and relates to the broader category of path traversal attacks that have been documented extensively in security literature. From an ATT&CK perspective, this vulnerability maps to techniques involving privilege escalation and persistence through file system manipulation. The mitigation strategies should include immediate patching of the GNU tar utility to remove the incorrect optimization and implement proper path validation. Organizations should also implement strict file access controls, regularly audit system files for unauthorized changes, and employ network segmentation to limit the potential impact of successful exploitation. Additionally, system administrators should disable automatic extraction of untrusted archives, implement proper input validation for archive processing, and consider using alternative archive handling tools that have been verified to properly address directory traversal concerns. The remediation process requires careful testing to ensure that the patched tar utility maintains compatibility with legitimate archive processing while eliminating the security flaw that allows arbitrary file overwrites.