CVE-2025-47219: GStreamer Information Disclosure Flaw

CVE-2025-47219 Overview

CVE-2025-47219 is an out-of-bounds read vulnerability [CWE-125] in the GStreamer multimedia framework through version 1.26.1. The flaw resides in the qtdemux_parse_trak function of the isomp4 plugin, which parses MP4 container files. A crafted MP4 file can cause the parser to read past the end of a heap buffer, potentially leaking adjacent heap memory contents to an attacker.

GStreamer is embedded in numerous Linux desktop environments, media players, and industrial systems, expanding the attack surface. Siemens has issued a separate advisory confirming downstream impact in industrial products.

Critical Impact

Remote attackers can deliver malicious MP4 files to trigger heap memory disclosure, potentially leaking sensitive process memory including pointers useful for bypassing address space layout randomization.

Affected Products

• GStreamer through version 1.26.1
• GStreamer isomp4 plugin (qtdemux element)
• Siemens products bundling vulnerable GStreamer versions (see SSA-032379)

Discovery Timeline

• 2025-08-07 - CVE-2025-47219 published to NVD
• 2026-05-12 - Last updated in NVD database

Technical Details for CVE-2025-47219

Vulnerability Analysis

The vulnerability is an out-of-bounds read in the qtdemux_parse_trak function inside the isomp4 plugin. This function processes track atoms (trak) within QuickTime and MP4 containers. When parsing malformed atom structures, the parser advances its read pointer past the bounds of the allocated heap buffer holding the input data.

Because MP4 parsing happens during demuxing, no user interaction beyond opening the file or rendering an embedded media element is required. Applications that automatically generate thumbnails or preview media, such as file managers and chat clients, can trigger parsing without explicit user action.

The disclosed memory may contain pointers, encryption keys, or other process data. While the primary impact is information disclosure, leaked pointers can support follow-on exploitation of separate memory corruption issues by defeating ASLR.

Root Cause

The root cause is insufficient bounds checking on size fields and offsets read from the MP4 container during trak atom parsing. The parser trusts attacker-controlled length values without validating them against the remaining buffer size, causing reads beyond the heap allocation.

Attack Vector

Exploitation requires delivering a crafted MP4 file to a system using a vulnerable GStreamer build. Delivery vectors include web pages embedding media, email attachments, messaging apps with media previews, and file managers performing automatic metadata extraction.

The vulnerability does not require authentication or local access. Detailed technical analysis is available in the Atredis Partners advisory.

Detection Methods for CVE-2025-47219

Indicators of Compromise

• Unexpected crashes or abnormal terminations of processes linked against libgstisomp4.so when handling media files
• MP4 files with malformed trak atom structures or inconsistent atom size fields
• Application logs from GStreamer-based players showing demuxer errors during qtdemux parsing

Detection Strategies

• Inventory installed GStreamer versions across endpoints and servers using package managers (dpkg -l gstreamer1.0-plugins-good, rpm -qa | grep gstreamer)
• Deploy file-content inspection to flag MP4 files with anomalous atom sizes arriving via email or web downloads
• Monitor for crashes in processes consuming the gst-plugins-good package, which contains isomp4

Monitoring Recommendations

• Audit endpoints for outdated GStreamer installations on Linux desktops, embedded devices, and industrial workstations
• Enable core dump collection on systems running media-handling applications to identify exploitation attempts
• Track network deliveries of MP4 content to high-value hosts using existing web and email security gateways

How to Mitigate CVE-2025-47219

Immediate Actions Required

• Update GStreamer to a version newer than 1.26.1 once the upstream patch is available from the GStreamer Security page
• Apply vendor-specific patches from downstream distributors and Siemens via the Siemens SSA-032379 advisory
• Restrict execution of media-processing utilities on servers that do not require multimedia handling

Patch Information

GStreamer publishes fixes through its official security tracker. Linux distributions including Debian, Ubuntu, Red Hat, and SUSE release rebuilt packages downstream. Industrial users should consult the Siemens ProductCERT advisory for affected device firmware updates.

Workarounds

• Disable or remove the isomp4 plugin where MP4 support is not required by deleting libgstisomp4.so from the GStreamer plugin directory
• Block ingestion of untrusted MP4 files at email and web proxies until patches are deployed
• Disable automatic media thumbnailing and preview features in file managers and chat clients on affected systems

# Remove the vulnerable isomp4 plugin (Debian/Ubuntu example)
sudo find / -name 'libgstisomp4.so' -exec mv {} {}.disabled \;

# Verify GStreamer version
gst-inspect-1.0 --version