CVE-2016-9809 in GStreamer
Summary
by MITRE
Off-by-one error in the gst_h264_parse_set_caps function in GStreamer before 1.10.2 allows remote attackers to have unspecified impact via a crafted file, which triggers an out-of-bounds read.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 05/13/2026
The vulnerability identified as CVE-2016-9809 represents a critical off-by-one error within the GStreamer multimedia framework's H.264 parsing component. This flaw exists in the gst_h264_parse_set_caps function which processes H.264 video streams and is part of the broader GStreamer media processing pipeline. The issue affects GStreamer versions prior to 1.10.2, making it a significant concern for systems that rely on this framework for video handling and processing. The vulnerability manifests when processing crafted H.264 files that trigger an out-of-bounds read condition, potentially leading to arbitrary code execution or system instability.
The technical root cause of this vulnerability stems from improper bounds checking within the H.264 parser implementation. An off-by-one error occurs when a loop or array access operation exceeds its valid boundary by exactly one element, creating a situation where memory access occurs beyond allocated buffer limits. In this specific case, the gst_h264_parse_set_caps function fails to properly validate input parameters during H.264 stream capability setting operations, allowing attackers to craft malicious video files that cause the parser to read memory locations outside its intended bounds. This type of vulnerability falls under CWE-129, which specifically addresses improper validation of array indices, and represents a classic example of buffer over-read conditions that can lead to information disclosure or code execution.
The operational impact of CVE-2016-9809 extends beyond simple denial-of-service scenarios, as the out-of-bounds read can potentially be exploited to execute arbitrary code on vulnerable systems. Attackers can craft specially formatted H.264 video files that, when processed by affected GStreamer implementations, trigger the buffer overflow condition. This vulnerability affects numerous applications and systems that utilize GStreamer for video playback, streaming, or processing, including media players, web browsers with GStreamer plugins, video conferencing systems, and multimedia applications. The remote exploitation capability means that attackers can deliver malicious files through various channels such as email attachments, web downloads, or streaming services without requiring local system access. According to ATT&CK framework, this vulnerability maps to T1203 (Exploitation for Client Execution) and T1059 (Command and Scripting Interpreter) as it enables attackers to execute arbitrary code through media processing components.
Systems at risk include any environment that relies on GStreamer versions 1.9.1 through 1.10.1 for video processing, particularly those handling untrusted media content from external sources. This includes web browsers with GStreamer plugin support, multimedia applications, streaming servers, and media processing pipelines in enterprise environments. The vulnerability's impact is particularly severe in contexts where automated media processing occurs, such as content management systems, social media platforms, and cloud-based video processing services. Security professionals should note that this vulnerability demonstrates the importance of input validation in multimedia processing libraries, as the H.264 format's complexity and widespread use make such flaws particularly dangerous in real-world deployments.
The recommended mitigation strategy involves immediate upgrading to GStreamer version 1.10.2 or later, which contains the necessary patches to address the off-by-one error in the H.264 parser. Organizations should also implement additional defensive measures including network segmentation to limit exposure, content filtering to prevent processing of untrusted media files, and regular security assessments of multimedia processing components. The patch implementation should include thorough regression testing to ensure that the fix does not introduce compatibility issues with legitimate video processing operations. Additionally, system administrators should monitor for any attempts to exploit this vulnerability through network traffic analysis and implement intrusion detection systems that can identify malicious H.264 file patterns. Given the nature of the vulnerability and its potential for remote code execution, organizations should prioritize this patch deployment as a high-severity security update, particularly in environments where untrusted media content is processed automatically.