CVE-2010-4054 in Gpl Ghostscript
Summary
by MITRE
The gs_type2_interpret function in Ghostscript allows remote attackers to cause a denial of service (incorrect pointer dereference and application crash) via crafted font data in a compressed data stream, aka bug 691043.
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Analysis
by VulDB Data Team • 08/01/2024
The vulnerability identified as CVE-2010-4054 resides within the Ghostscript document processing library, specifically in the gs_type2_interpret function that handles Type 2 font interpretation. This function processes font data within compressed data streams, making it a critical component in the rendering pipeline for PDF and PostScript documents. The flaw manifests when the system encounters crafted font data that triggers an incorrect pointer dereference, leading to an application crash and subsequent denial of service condition. This vulnerability represents a classic buffer over-read scenario where the interpreter fails to properly validate font data structures before accessing memory locations, resulting in unpredictable application behavior.
The technical implementation of this vulnerability stems from inadequate input validation within the font parsing mechanism. When Ghostscript processes compressed font data containing maliciously crafted sequences, the gs_type2_interpret function attempts to dereference pointers that either point to invalid memory locations or have been improperly initialized. This incorrect pointer manipulation typically occurs during the interpretation phase of Type 2 fonts, which are commonly used in PDF documents and PostScript files. The vulnerability is particularly concerning because it can be triggered through normal document processing workflows, requiring no special privileges or user interaction beyond viewing a maliciously crafted document. The flaw falls under CWE-476 which specifically addresses NULL pointer dereference conditions, and the attack pattern aligns with ATT&CK technique T1203 - Exploitation for Client Execution, where adversaries leverage application vulnerabilities to cause service disruption.
From an operational impact perspective, this vulnerability creates significant risks for organizations relying on Ghostscript for document processing, particularly in environments where PDF and PostScript files are frequently handled. The denial of service condition affects any system running Ghostscript versions vulnerable to this flaw, potentially disrupting document rendering services, print queues, and automated processing systems. Attackers can exploit this vulnerability remotely by preparing malicious font data that, when processed by a vulnerable Ghostscript instance, will cause the application to crash and terminate unexpectedly. The impact extends beyond simple service disruption to potentially affect business continuity when document processing systems become unavailable, especially in enterprise environments where print servers and document management systems depend on Ghostscript functionality. The vulnerability also presents challenges for system administrators who must maintain service availability while patching affected systems, as the crash condition can occur at any point during document processing, making detection and prevention difficult.
Mitigation strategies for CVE-2010-4054 primarily focus on immediate patching of affected Ghostscript installations, with system administrators prioritizing updates from the official Ghostscript project or their respective operating system vendors. Organizations should implement network segmentation and access controls to limit exposure of vulnerable systems to untrusted document sources, particularly in environments where users may encounter unknown or potentially malicious PDF files. Input validation measures can be enhanced by configuring Ghostscript to process documents through additional sanitization layers that validate font data before it reaches the vulnerable interpreter. Security monitoring should include detection of application crashes and unexpected terminations of Ghostscript processes, as these events may indicate exploitation attempts. Additionally, organizations should consider implementing sandboxing techniques for document processing to contain potential exploitation attempts and prevent cascading failures within their document handling infrastructure. The remediation process should also include comprehensive testing of patched systems to ensure that the vulnerability is fully addressed without introducing regressions in document processing functionality.