CVE-2007-6731 in Extended Module Player
Summary
by MITRE
Extended Module Player (XMP) 2.5.1 and earlier allow remote attackers to execute arbitrary code via an OXM file with a negative value, which bypasses a check in (1) test_oxm and (2) decrunch_oxm functions in misc/oxm.c, leading to a buffer overflow.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 12/15/2024
The Extended Module Player (XMP) vulnerability identified as CVE-2007-6731 represents a critical buffer overflow flaw affecting versions 2.5.1 and earlier of this multimedia playback software. This vulnerability specifically targets the handling of OXM (Open XMS Module) files, which are used for storing musical compositions in a format compatible with the Open XMS module system. The flaw manifests when the software processes malformed OXM files containing negative values that bypass crucial validation checks within the codebase.
The technical implementation of this vulnerability occurs within the misc/oxm.c source file where two distinct functions - test_oxm and decrunch_oxm - fail to properly validate input parameters. When an attacker crafts an OXM file with negative values, these functions do not adequately verify the legitimacy of such parameters before proceeding with buffer operations. This oversight creates a condition where the software attempts to allocate memory or perform operations based on invalid negative values, ultimately leading to a buffer overflow scenario. The vulnerability stems from insufficient bounds checking and input validation mechanisms that should have prevented the execution of malformed data processing routines.
The operational impact of this vulnerability extends beyond simple code execution, as it provides remote attackers with the capability to achieve arbitrary code execution on systems running affected versions of XMP. This represents a significant security risk since users may unknowingly open malicious OXM files through various attack vectors including email attachments, web downloads, or file sharing platforms. The buffer overflow condition creates opportunities for attackers to overwrite critical memory locations, potentially allowing them to inject and execute malicious code with the privileges of the affected application. This could result in complete system compromise, data exfiltration, or the establishment of persistent backdoors within the target environment.
Mitigation strategies for this vulnerability require immediate patching of affected XMP installations to versions that address the buffer overflow conditions in the test_oxm and decrunch_oxm functions. System administrators should implement strict file validation policies that prevent automatic execution of potentially malicious media files, particularly those originating from untrusted sources. Network security controls including intrusion detection systems and file integrity monitoring should be deployed to detect and prevent exploitation attempts. Organizations should also consider implementing sandboxing mechanisms for media file processing and establishing robust patch management procedures to ensure timely remediation of similar vulnerabilities. This vulnerability aligns with CWE-121, which describes the weakness of stack-based buffer overflow, and represents a typical example of how insufficient input validation can create remote code execution opportunities in multimedia processing applications.
The broader implications of this vulnerability extend to the software security community's understanding of multimedia format parsing risks. It demonstrates how seemingly benign file format specifications can become attack vectors when proper input validation and bounds checking are absent from the implementation. The attack surface for such vulnerabilities often includes not just the primary application but also the ecosystem of systems that process these files, making comprehensive mitigation strategies essential for overall security posture. This case study reinforces the importance of applying the principle of least privilege and defensive programming practices when developing applications that handle external file formats.