CVE-2005-3192 in Xpdf
Summary
by MITRE
Heap-based buffer overflow in the StreamPredictor function in Xpdf 3.01, as used in products such as (1) Poppler, (2) teTeX, (3) KDE kpdf, and (4) pdftohtml, (5) KOffice KWord, (6) CUPS, and (7) libextractor allows remote attackers to execute arbitrary code via a PDF file with an out-of-range numComps (number of components) field.
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Analysis
by VulDB Data Team • 07/06/2021
The vulnerability identified as CVE-2005-3192 represents a critical heap-based buffer overflow affecting Xpdf 3.01 library implementations across multiple software ecosystems. This flaw resides within the StreamPredictor function which processes PDF data streams, specifically when handling the numComps field that defines the number of components in a PDF stream. The vulnerability manifests when a malicious PDF file contains an out-of-range numComps value that exceeds the allocated buffer boundaries, creating a condition where arbitrary data can be written beyond the intended memory allocation. This issue impacts a broad range of applications including Poppler, teTeX, KDE kpdf, pdftohtml, KOffice KWord, CUPS, and libextractor, demonstrating the widespread adoption and reliance on this vulnerable library component. The flaw falls under CWE-121, heap-based buffer overflow, and aligns with ATT&CK technique T1059.007 for command and scripting interpreter execution, as successful exploitation could enable remote code execution.
The technical exploitation of this vulnerability occurs when a PDF document with malformed numComps field values triggers the StreamPredictor function to write data beyond allocated heap memory regions. The out-of-range value causes the function to attempt memory writes that exceed buffer boundaries, potentially overwriting adjacent memory structures including return addresses, function pointers, or other critical data. Attackers can craft malicious PDF files that, when processed by vulnerable applications, cause the buffer overflow to redirect program execution flow or inject malicious code into the target system. The heap-based nature of this vulnerability means that memory corruption occurs in the heap allocation space rather than the stack, making exploitation more complex but still highly effective. This type of vulnerability is particularly dangerous in applications that process untrusted PDF content, such as web browsers, document viewers, and print systems.
The operational impact of CVE-2005-3192 extends across multiple attack vectors and system environments where vulnerable software components are deployed. Applications that handle PDF processing in web environments, print servers, or document management systems become prime targets for exploitation, potentially allowing attackers to gain remote code execution privileges. The vulnerability affects both desktop applications and server-side processing systems, creating risk across enterprise environments where PDF handling is common. Organizations using affected versions of Poppler, CUPS, or KDE applications face significant exposure, as these components are often integrated into larger software stacks and network services. The widespread adoption of Xpdf 3.01 across different software platforms amplifies the potential attack surface, with each vulnerable application representing a possible entry point for malicious actors. Security implications include data breaches, system compromise, and potential lateral movement within network environments where these vulnerable applications are deployed.
Mitigation strategies for CVE-2005-3192 require immediate patching of affected software versions and implementation of input validation controls. Organizations should prioritize updating to patched versions of Xpdf libraries and all affected applications including Poppler, CUPS, and KDE components. Input sanitization measures should be implemented to validate numComps field values before processing, ensuring that component counts fall within acceptable ranges. Memory protection mechanisms such as stack canaries, address space layout randomization, and data execution prevention should be enabled to reduce exploitability. Network segmentation and application whitelisting can help limit the impact of successful exploitation attempts. Regular vulnerability assessments should be conducted to identify and remediate similar buffer overflow vulnerabilities in other PDF processing libraries. The remediation process should include comprehensive testing to ensure that patched versions maintain functionality while eliminating the buffer overflow conditions that enable exploitation. Additionally, implementing sandboxing techniques for PDF processing and restricting user privileges when handling PDF documents can provide additional defense-in-depth measures against potential exploitation attempts.