Heap Buffer Overflow Vulnerability in VLC Media Player
Summary
OSV-2026-57: Heap-buffer-overflow in mkv::matroska_segment_c::TrackInit. Affects vlc versions >= f8e9d090fc20452cfddb91df28bf235eb59baff1, < 643b5a278f40a899d0c981499da70a0721e1dff5. Fixed in 643b5a278f40a899d0c981499da70a0721e1dff5. How to fix ↓
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Background
VLC Media Player is a widely used open-source multimedia player that supports various audio and video formats. It is known for its versatility, user-friendly interface, and ability to play almost any media file without the need for additional codecs. However, like many software applications, VLC is not immune to vulnerabilities. The specific issue at hand is a heap buffer overflow that can occur during the processing of Matroska (MKV) files, potentially leading to crashes or exploitation.
Vulnerability Detail
The vulnerability identified as a heap buffer overflow occurs in the function mkv::matroska_segment_c::TrackInit within the VLC codebase. This issue was reported through OSS-Fuzz, indicating that it can lead to a crash when processing malformed MKV files. The crash state reveals that the overflow happens during the initialization of track entries, which could allow an attacker to exploit this flaw to execute arbitrary code or cause denial of service. The severity of this vulnerability is classified as HIGH, making it critical for users to address it promptly.
How To Fix
Minimum fixed version
643b5a278f40a899d0c981499da70a0721e1dff5
This is the first release that contains the fix.
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Workaround
As a temporary workaround, users can avoid opening MKV files that are from untrusted sources until the patch is applied. Additionally, users can consider using alternative media players that do not exhibit this vulnerability.
Conclusion
The heap buffer overflow vulnerability in VLC Media Player poses a significant risk to users, particularly when handling MKV files. It is crucial for users to update to the latest patched version to mitigate this risk. By following the provided steps and utilizing tools like Vulert, users can ensure their software remains secure.
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FAQ
A heap buffer overflow occurs when a program writes more data to a buffer located on the heap than it can hold, potentially leading to data corruption, crashes, or security vulnerabilities.
You can check your VLC version by opening the application and navigating to 'Help' > 'About'. If your version is between the introduced and fixed ranges, it is affected.
While the primary risk is a crash or potential code execution, there is also a risk of data loss if the application crashes while processing files.
Yes, Vulert can monitor your software for open-source vulnerabilities in real-time using just a manifest file like package-lock.json. You can check your application against known vulnerabilities without needing to install any software.
If you cannot update VLC right away, avoid opening MKV files from untrusted sources and consider using alternative media players until you can apply the patch.
References
Related vulnerabilities
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