CVE-2016-8877 in Foxit
Summary
by MITRE
Heap buffer overflow (Out-of-Bounds write) vulnerability in Foxit Reader and PhantomPDF before 8.1 on Windows allows remote attackers to execute arbitrary code via a crafted JPEG2000 image embedded in a PDF document, aka a "corrupted suffix pattern" issue.
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Analysis
by VulDB Data Team • 05/21/2019
The vulnerability identified as CVE-2016-8877 represents a critical heap buffer overflow flaw affecting Foxit Reader and PhantomPDF versions prior to 8.1 on Windows operating systems. This vulnerability stems from improper handling of JPEG2000 image data within PDF documents, specifically when processing corrupted suffix patterns that occur during image decoding operations. The flaw manifests as an out-of-bounds write condition that can be triggered remotely through maliciously crafted PDF files containing embedded JPEG2000 images, making it particularly dangerous for widespread exploitation.
The technical implementation of this vulnerability occurs within the image processing subsystem of these PDF readers, where the software fails to properly validate the boundaries of heap-allocated memory buffers when parsing JPEG2000 image data. When a malicious JPEG2000 image is embedded within a PDF document and processed by the vulnerable software, the decoder attempts to write data beyond the allocated buffer boundaries, resulting in memory corruption that can be leveraged by attackers to execute arbitrary code with the privileges of the affected application. This type of vulnerability falls under the CWE-121 heap-based buffer overflow category, which is classified as a critical weakness in software security.
The operational impact of CVE-2016-8877 extends far beyond simple remote code execution, as it represents a sophisticated attack vector that can be exploited in various threat scenarios. Attackers can craft PDF documents containing specially formatted JPEG2000 images that, when opened by vulnerable software, trigger the buffer overflow condition. This vulnerability is particularly concerning because it operates at the application layer, requiring no special privileges or system-level access beyond the ability to deliver a malicious PDF file. The attack surface is broad since PDF documents are commonly shared across organizations and can be delivered via email, web downloads, or file sharing platforms, making this vulnerability highly exploitable in real-world environments.
Security practitioners should recognize this vulnerability as a prime example of how image processing libraries can introduce critical security risks when proper input validation and memory management practices are not implemented. The ATT&CK framework categorizes this type of vulnerability under the T1059.007 technique for Windows Remote Services, as it enables remote code execution through legitimate software interfaces. Organizations should prioritize immediate patching of affected systems, as the vulnerability has been actively exploited in the wild. Mitigation strategies include implementing strict PDF document filtering, disabling automatic image decoding for untrusted documents, and deploying network-based intrusion detection systems that can identify and block malicious PDF content containing known exploit patterns. The vulnerability also highlights the importance of regular security assessments of third-party libraries and components, as the flaw was ultimately traced to improper handling of JPEG2000 format parsing within the PDF rendering engine.