CVE-2023-7216 in cpio
Summary
by MITRE • 02/05/2024
A path traversal vulnerability was found in the CPIO utility. This issue could allow a remote unauthenticated attacker to trick a user into opening a specially crafted archive. During the extraction process, the archiver could follow symlinks outside of the intended directory, which allows files to be written in arbitrary directories through symlinks.
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Analysis
by VulDB Data Team • 02/26/2026
The CVE-2023-7216 vulnerability represents a critical path traversal flaw within the CPIO (Copy Input/Output) utility, a fundamental tool used for creating and extracting archive files in Unix-like operating systems. This vulnerability specifically affects the archive extraction process where the utility fails to properly validate symbolic link targets, allowing attackers to manipulate file placement during decompression operations. The flaw exists in how CPIO handles symbolic links when extracting archives, creating a scenario where maliciously crafted archives can cause the utility to write files outside of the intended extraction directory. This issue is particularly concerning as CPIO is widely used across various systems and applications for handling archive operations, making it a prime target for exploitation. The vulnerability stems from inadequate input validation and path resolution mechanisms within the utility's extraction logic, which does not sufficiently restrict symbolic link resolution to prevent escape from designated boundaries.
The technical exploitation of this vulnerability occurs when a user or application extracts a maliciously crafted CPIO archive without proper safeguards. During the extraction process, the utility encounters symbolic links that point outside the intended extraction directory, allowing the attacker to control where files are written on the target system. This path traversal behavior enables attackers to overwrite critical system files, create backdoor executables in privileged directories, or place malicious components in locations where they can be executed with elevated privileges. The vulnerability is particularly dangerous because it can be triggered through seemingly benign archive files that appear legitimate to users. The flaw essentially allows attackers to bypass normal file system access controls by leveraging the natural behavior of symbolic links to redirect file placement. This creates a direct pathway for privilege escalation and arbitrary code execution when the extracted files are subsequently executed or when the attacker places malicious components in system directories.
The operational impact of CVE-2023-7216 extends far beyond simple file placement issues, as it can lead to complete system compromise when exploited in conjunction with other attack vectors. Organizations relying on CPIO for package management, system updates, or backup restoration operations face significant risk from this vulnerability. Attackers can leverage this flaw to place malicious binaries in system paths such as /usr/bin or /bin directories, potentially gaining persistent access to compromised systems. The vulnerability is especially dangerous in automated environments where archive extraction occurs without user intervention, as it can silently compromise systems during routine operations. This flaw aligns with CWE-22 Path Traversal and follows patterns consistent with ATT&CK technique T1059 Command and Scripting Interpreter, as it enables attackers to execute malicious code through manipulated archive contents. The vulnerability also relates to ATT&CK technique T1548.001 Valid Accounts as it can be exploited to escalate privileges and gain access to system resources that would otherwise be restricted.
Mitigation strategies for CVE-2023-7216 require both immediate patching and operational security improvements. System administrators should prioritize updating CPIO utilities to versions that address the path traversal vulnerability, typically through package manager updates or direct vendor patches. Organizations should implement strict archive validation policies that scan archives for suspicious symbolic link patterns before extraction. The use of sandboxed extraction environments can help contain potential path traversal attempts by limiting the file system access during archive operations. Additionally, implementing proper file system permissions and directory restrictions can help prevent successful exploitation even if the vulnerability is not patched immediately. Organizations should also consider disabling automatic extraction of untrusted archives and implementing manual review processes for archive contents. The vulnerability highlights the importance of secure coding practices for system utilities and reinforces the need for regular security assessments of core system tools. Network segmentation and monitoring for suspicious archive extraction activities can provide early detection of potential exploitation attempts. Security teams should also review and update their incident response procedures to address potential compromise scenarios arising from this vulnerability, particularly focusing on monitoring for unauthorized file creation in system directories and unusual symbolic link creation patterns.