CVE-2024-0444: GStreamer AV1 Parsing RCE Vulnerability

CVE-2024-0444 Overview

CVE-2024-0444 is a stack-based buffer overflow vulnerability in GStreamer, the popular open-source multimedia framework. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GStreamer. While interaction with the library is required to exploit this vulnerability, attack vectors may vary depending on the implementation.

The specific flaw exists within the parsing of tile list data within AV1-encoded video files. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. This vulnerability was tracked as ZDI-CAN-22873 by the Zero Day Initiative.

Critical Impact

Remote code execution via maliciously crafted AV1 video files could allow attackers to gain full control of systems running GStreamer-based applications.

Affected Products

• GStreamer Project GStreamer (all versions prior to patch)
• Applications and systems utilizing the GStreamer multimedia framework
• Linux distributions and media players leveraging GStreamer for AV1 video decoding

Discovery Timeline

• 2024-06-07 - CVE-2024-0444 published to NVD
• 2024-12-27 - Last updated in NVD database

Technical Details for CVE-2024-0444

Vulnerability Analysis

This vulnerability represents a classic stack-based buffer overflow (CWE-121) combined with out-of-bounds write (CWE-787) in GStreamer's AV1 codec parsing functionality. The flaw manifests when the parser processes tile list data embedded within AV1-encoded video files.

When GStreamer processes an AV1 video stream, it parses various metadata structures including tile configurations. The vulnerable code path fails to properly validate the size of user-controlled tile list data before copying it to a fixed-length buffer allocated on the stack. This creates a condition where an attacker can overflow the buffer boundaries, corrupting adjacent stack memory including return addresses and saved frame pointers.

The vulnerability is particularly concerning because GStreamer is widely deployed across Linux desktop environments, embedded systems, and multimedia applications. Any application that processes AV1 video content using GStreamer could potentially be exploited.

Root Cause

The root cause of CVE-2024-0444 lies in insufficient input validation within the AV1 parsing code. Specifically, the parser does not verify that the length of tile list data received from the video stream fits within the allocated stack buffer before performing the copy operation. This missing bounds check allows attackers to craft AV1 video files with oversized tile list entries that exceed the buffer capacity, resulting in stack memory corruption.

Attack Vector

The attack vector is network-based, requiring user interaction to trigger the vulnerability. An attacker could exploit this vulnerability through several scenarios:

1. Malicious Video Files: Distributing specially crafted AV1 video files through file sharing, email attachments, or downloads
2. Web-Based Attacks: Embedding malicious AV1 content in web pages that trigger GStreamer-based video playback
3. Streaming Content: Serving malicious AV1 streams through compromised or attacker-controlled media servers
4. Media Processing Pipelines: Targeting automated systems that process user-uploaded video content

The vulnerability is triggered when the victim opens or plays the malicious AV1 video file using any application that relies on GStreamer for media decoding. Successful exploitation allows the attacker to execute arbitrary code with the privileges of the process running GStreamer.

Detection Methods for CVE-2024-0444

Indicators of Compromise

• Unexpected crashes in GStreamer-based applications, particularly when processing AV1 video content
• Stack smashing or buffer overflow detection alerts from system security mechanisms (ASLR, stack canaries)
• Anomalous process behavior following video file playback, such as unexpected network connections or child process spawning
• Core dumps or crash logs indicating memory corruption in GStreamer AV1 parsing functions

Detection Strategies

• Monitor for abnormal process behavior in applications using GStreamer when processing AV1 media files
• Deploy endpoint detection solutions capable of identifying memory corruption exploitation attempts
• Implement file integrity monitoring on GStreamer library files to detect unauthorized modifications
• Use sandboxing technologies to isolate media processing and limit the impact of successful exploitation

Monitoring Recommendations

• Enable crash reporting and analysis for GStreamer-dependent applications to identify potential exploitation attempts
• Monitor system logs for segmentation faults or memory access violations in multimedia processing contexts
• Implement network traffic analysis to detect delivery of potentially malicious AV1 video content
• Configure SentinelOne agents to detect and respond to anomalous behavior patterns associated with RCE exploitation

How to Mitigate CVE-2024-0444

Immediate Actions Required

• Update GStreamer to the latest patched version immediately across all affected systems
• Audit all applications and systems that utilize GStreamer for AV1 video processing
• Consider temporarily disabling AV1 codec support in GStreamer if patching is not immediately possible
• Implement application sandboxing for media players and video processing applications

Patch Information

The GStreamer project has released a security patch to address this vulnerability. The fix involves adding proper bounds checking for tile list data length before copying to the stack buffer. The patch is available in the GitLab GStreamer repository with commit hash f368d63ecd89e01fd2cf0b1c4def5fc782b2c390.

Organizations should apply this patch through their distribution's package management system or by updating to a GStreamer release that includes this fix. For detailed technical information about the vulnerability, refer to the Zero Day Initiative Advisory ZDI-24-567.

Workarounds

• Disable AV1 codec plugins in GStreamer by removing or renaming the relevant plugin files until patching is possible
• Implement strict input validation and file type filtering to prevent processing of untrusted AV1 video content
• Deploy application-level sandboxing using technologies like Flatpak, Snap, or containerization to limit exploitation impact
• Configure firewalls and content filters to block AV1 video content from untrusted sources

# Disable GStreamer AV1 plugin as temporary workaround
# Locate and rename the AV1 codec plugin to prevent loading
sudo find /usr/lib -name "*gstav1*" -exec mv {} {}.disabled \;

# Verify the plugin is no longer loaded
gst-inspect-1.0 | grep -i av1