CVE-2003-0434 in Mandrake Linux
Summary
by MITRE
Various PDF viewers including (1) Adobe Acrobat 5.06 and (2) Xpdf 1.01 allow remote attackers to execute arbitrary commands via shell metacharacters in an embedded hyperlink.
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Analysis
by VulDB Data Team • 12/15/2024
This vulnerability represents a critical command injection flaw in PDF document viewers that enables remote code execution through maliciously crafted hyperlinks. The vulnerability affects major PDF rendering applications including Adobe Acrobat 5.06 and Xpdf 1.01, demonstrating the widespread nature of this security issue across different software implementations. The flaw occurs when these applications process embedded hyperlinks without proper sanitization of shell metacharacters, creating an attack surface where malicious actors can inject arbitrary commands that get executed by the underlying operating system.
The technical implementation of this vulnerability stems from improper input validation and sanitization within the PDF viewer's hyperlink processing functionality. When a PDF document contains a hyperlink with shell metacharacters such as semicolons, ampersands, or backticks, the vulnerable applications fail to properly escape or filter these characters before passing the URL to the system shell for execution. This design flaw allows attackers to craft malicious PDF documents that, when opened, automatically execute arbitrary commands on the victim's system. The vulnerability operates at the application layer and can be exploited remotely without requiring user interaction beyond opening the malicious document, making it particularly dangerous in phishing scenarios or automated attack campaigns.
The operational impact of CVE-2003-0434 is severe and multifaceted, as it provides attackers with complete system compromise capabilities. Successful exploitation can lead to full system control, data exfiltration, privilege escalation, and persistent backdoor installation. The vulnerability affects both Windows and Unix-like systems where these PDF viewers are deployed, with the attack surface extending to any environment where users might encounter PDF documents from untrusted sources. Organizations relying on these applications for document sharing, legal proceedings, or business communications face significant risk exposure, as the vulnerability can be exploited through email attachments, web downloads, or shared network resources.
From a cybersecurity perspective, this vulnerability aligns with CWE-78 which describes improper neutralization of special elements used in OS commands, and maps to ATT&CK technique T1059.007 for command and scripting interpreter. The attack chain typically begins with social engineering to deliver the malicious PDF, followed by exploitation of the command injection vulnerability to execute arbitrary code with the privileges of the PDF viewer process. Mitigation strategies include immediate patching of affected software versions, implementing strict network controls to filter PDF content, disabling automatic hyperlink execution, and deploying application whitelisting solutions. Organizations should also consider network segmentation, user education programs, and regular security assessments to reduce the risk of exploitation. The vulnerability highlights the importance of proper input validation and the principle of least privilege in application design, particularly for software that processes untrusted content from external sources.