Fuzzing Windows Media Foundation in 2021

on YouTube ↗27m

" summary

Fuzzing targets the Windows Media Foundation codec DLL that enables WebM playback via a custom harness and corpus of ~1,000 WebM files (1 KB–1 MB) run on multiple VMs with fast RAM and SSDs, using mutation-based generators and WinDbg/WinDbg Preview for triage. Results: 10,000 crashes reduced to 23 unique issues and 2 critical RCEs, discovered within a six‑month, six months running 24/7 campaign and reported to Microsoft leading to CVEs on Patch Tuesday.

AI-written summary · about

" chapters (9)

1. 0:00Introduction
2. 0:32About me
3. 1:31Flow of fuzzing
4. 4:08Windows Media Player
5. 5:28File Format
6. 10:19Fuzzing
7. 17:35Webm
8. 19:47Results
9. 22:26Lessons Learned

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