CVE-2009-4015 in Lintian
Summary
by MITRE
Lintian 1.23.x through 1.23.28, 1.24.x through 1.24.2.1, and 2.x before 2.3.2 allows remote attackers to execute arbitrary commands via shell metacharacters in filename arguments.
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Analysis
by VulDB Data Team • 04/29/2026
The vulnerability identified as CVE-2009-4015 affects Lintian versions 1.23.x through 1.23.28, 1.24.x through 1.24.2.1, and 2.x versions before 2.3.2. This represents a critical command injection flaw that allows remote attackers to execute arbitrary code on systems running vulnerable versions of the package analyzer. Lintian serves as a tool for checking Debian packages for common errors and policy violations, making it a critical component in the Debian packaging ecosystem and software distribution pipeline. The vulnerability specifically arises from insufficient input sanitization when processing filename arguments, creating a path for malicious actors to inject shell metacharacters that get interpreted by the underlying shell during package processing operations.
The technical flaw stems from improper handling of user-supplied input within the command execution context of Lintian. When the tool processes package filenames containing shell metacharacters such as semicolons, ampersands, or backticks, these characters are not properly escaped or sanitized before being passed to shell commands. This behavior directly maps to CWE-78, which describes improper neutralization of special elements used in OS commands, and aligns with ATT&CK technique T1059.001 for executing malicious commands through command-line interfaces. The vulnerability creates a direct path for arbitrary code execution because the application constructs shell commands by concatenating user-provided filenames without proper input validation or sanitization mechanisms.
The operational impact of this vulnerability is severe as it enables remote code execution in environments where Lintian is used for package analysis, particularly in automated build systems, continuous integration pipelines, or package repositories. Attackers could exploit this vulnerability by crafting malicious package filenames containing shell metacharacters, which when processed by the vulnerable Lintian version would result in arbitrary command execution with the privileges of the user running the tool. This could lead to complete system compromise, data exfiltration, or disruption of package building and distribution processes. The vulnerability is particularly dangerous in automated environments where package analysis tools run without manual oversight, as it could be exploited through package submission mechanisms or automated package verification systems.
Mitigation strategies for CVE-2009-4015 involve immediate upgrading to Lintian versions 2.3.2 or later, which contain the necessary input sanitization patches. Organizations should also implement strict input validation for all filename arguments processed by Lintian, ensuring that special shell characters are properly escaped or removed before command execution occurs. Security monitoring should be enhanced to detect unusual command execution patterns or attempts to inject shell metacharacters into package analysis workflows. The fix implemented in patched versions addresses the root cause by properly sanitizing input before shell command construction, following secure coding practices that prevent command injection vulnerabilities. System administrators should also consider implementing network segmentation and access controls to limit exposure of systems running vulnerable Lintian versions, while maintaining regular security updates to prevent similar vulnerabilities in other tools within the software supply chain.