CVE-2026-3086 in GStreamer
Summary
by MITRE • 03/16/2026
GStreamer H.266 Codec Parser Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GStreamer. Interaction with this library is required to exploit this vulnerability but attack vectors may vary depending on the implementation.
The specific flaw exists within the processing of APS units. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-28911.
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Analysis
by VulDB Data Team • 04/14/2026
The CVE-2026-3086 vulnerability represents a critical out-of-bounds write flaw within the GStreamer H.266 codec parser that poses significant security risks to affected systems. This vulnerability resides in the processing of APS (Application Parameter Set) units within the H.266 video codec implementation, making it particularly dangerous given the widespread use of GStreamer in multimedia applications and streaming platforms. The vulnerability was identified as ZDI-CAN-28911 and demonstrates the ongoing challenges in securing multimedia codec parsers where improper input validation can lead to remote code execution.
The technical root cause of this vulnerability stems from insufficient validation of user-supplied data during the parsing of H.266 codec structures. When the GStreamer library processes APS units, it fails to properly validate the size and boundaries of incoming data, leading to a scenario where an attacker can craft malicious input that causes the parser to write data beyond the allocated buffer boundaries. This type of flaw falls under CWE-787, which specifically addresses out-of-bounds write conditions that can result in memory corruption and arbitrary code execution. The vulnerability's exploitation requires interaction with the GStreamer library, making it particularly concerning for applications that process untrusted multimedia content.
The operational impact of this vulnerability extends beyond simple remote code execution, as it can potentially allow attackers to gain full control over affected systems running vulnerable versions of GStreamer. The attack vector varies depending on the specific implementation and deployment of the library, but typically involves an attacker sending specially crafted H.266 video streams to a target system that processes such media. This vulnerability affects any system that utilizes GStreamer's H.266 codec parser, including media servers, streaming platforms, and multimedia applications that handle video content. The remote code execution capability means that an attacker could potentially install malware, modify system files, or establish persistent access to compromised systems.
Mitigation strategies for CVE-2026-3086 should prioritize immediate patching of affected GStreamer installations, as this represents a critical vulnerability that can be exploited without user interaction. Organizations should implement network segmentation and monitoring to detect suspicious media traffic patterns that might indicate exploitation attempts. Additionally, deploying input validation controls at network boundaries and application layers can provide defense-in-depth protection. The vulnerability's classification aligns with ATT&CK technique T1059.007, which covers command and scripting interpreter execution, as successful exploitation would likely involve executing malicious code within the target process context. System administrators should also consider implementing automated vulnerability scanning and patch management processes to prevent similar issues in other multimedia libraries and codecs that may share similar architectural flaws.