CVE-2009-0791 in CUPS
Summary
by MITRE
Multiple integer overflows in Xpdf 2.x and 3.x and Poppler 0.x, as used in the pdftops filter in CUPS 1.1.17, 1.1.22, and 1.3.7, GPdf, and kdegraphics KPDF, allow remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a crafted PDF file that triggers a heap-based buffer overflow, possibly related to (1) Decrypt.cxx, (2) FoFiTrueType.cxx, (3) gmem.c, (4) JBIG2Stream.cxx, and (5) PSOutputDev.cxx in pdftops/. NOTE: the JBIG2Stream.cxx vector may overlap CVE-2009-1179.
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Analysis
by VulDB Data Team • 09/05/2019
The vulnerability described in CVE-2009-0791 represents a critical class of integer overflow flaws affecting multiple PDF processing libraries and applications. This vulnerability impacts Xpdf versions 2.x and 3.x, Poppler 0.x, and various applications that utilize the pdftops filter in CUPS 1.1.17, 1.1.22, and 1.3.7, along with GPdf and KDE graphics KPDF. The flaw stems from improper handling of integer values during PDF parsing operations, creating conditions where maliciously crafted PDF files can trigger unexpected behavior in the underlying software components.
The technical implementation of this vulnerability involves multiple source files within the affected libraries, specifically Decrypt.cxx, FoFiTrueType.cxx, gmem.c, JBIG2Stream.cxx, and PSOutputDev.cxx within the pdftops component. These files handle different aspects of PDF processing including decryption operations, TrueType font handling, memory management, JBIG2 image stream processing, and PostScript output generation. When these components process malformed PDF data containing oversized integer values, they fail to properly validate input parameters, leading to integer overflow conditions that subsequently result in heap-based buffer overflows. The vulnerability is particularly dangerous because it can potentially allow remote code execution rather than merely causing denial of service.
From an operational perspective, this vulnerability creates significant risk for organizations relying on PDF processing capabilities across their infrastructure. The attack vector requires only a malicious PDF file to be processed by any of the affected applications, making it highly exploitable in real-world scenarios. The potential for remote code execution means that attackers could gain unauthorized access to systems processing PDF documents, particularly affecting print servers, web applications, and document management systems. The overlap with CVE-2009-1179 indicates that similar vulnerabilities exist in the JBIG2 processing component, suggesting a broader pattern of integer overflow issues within the PDF processing libraries. This vulnerability directly maps to CWE-190, Integer Overflow or Wraparound, and CWE-129, Improper Validation of Array Index, which are fundamental weaknesses in software security design.
The impact of exploitation manifests through both denial of service and potential code execution scenarios. In denial of service cases, applications crash due to memory corruption caused by buffer overflows, rendering PDF processing capabilities unavailable to legitimate users. However, the possibility of arbitrary code execution makes this vulnerability particularly concerning, as it could enable attackers to execute malicious payloads on vulnerable systems. The affected applications represent critical infrastructure components in many organizations, making the potential for widespread compromise significant. Organizations should consider implementing network segmentation, content filtering, and regular security updates to mitigate exposure to this vulnerability. The ATT&CK framework categorizes this as a vulnerability exploitation technique, specifically targeting software flaws in document processing components, with potential for privilege escalation and lateral movement within compromised networks.