CVE-2024-47835

What it actually does

Null pointer dereference in parse_lrc within gstsubparse.c: strchr() search for ']' returns NULL on malformed input, which is then passed to g_strdup(start + 1) causing immediate crash.

Why it matters to the business

Media playback or processing applications using GStreamer become unavailable when handling certain subtitle-containing files, leading to service interruptions for content delivery or editing workflows.

How an attack unfolds

An attacker crafts an LRC subtitle string lacking the expected ']' character and embeds it in a media file or stream; when GStreamer parses the subtitles during playback or processing, the null dereference occurs and terminates the process.

How to fix it

Upgrade GStreamer to a build containing commit 5be4b6f03689ab438822f6cfcd13f1f300afe203 (equivalent to release 1.24.10 or newer) on all affected systems; rebuild any dependent applications against the patched library.

How to confirm the fix worked

Confirm the installed GStreamer version reports a commit after 5be4b6f or 1.24.10+; test by feeding a crafted LRC line missing ']' through gstsubparse and verify no crash occurs.

Typical attack path

1. Create or modify an LRC subtitle line without a closing ']' bracket
2. Package the malformed subtitle into a supported media container or stream
3. Deliver the file or stream to a target application that uses GStreamer for subtitle parsing
4. Trigger subtitle parsing (e.g., via playback or metadata inspection) to induce the crash

How to detect it

Monitor application and system logs for segmentation faults or crashes originating from gstsubparse or libgstreamer processes during media file handling; correlate with file opens involving .lrc or subtitle metadata.

What your security team should do

• Prioritize patching GStreamer to the fixed commit across all media-handling pipelines within the next maintenance window
• Inventory and replace any statically linked or vendored copies of the library
• Add automated build checks to ensure future GStreamer updates are tracked and deployed promptly