Jetset: Targeted Firmware Rehosting for Embedded Systems

By Willy R. Vasquez, Stephen Checkoway, and Hovav Shacham.

In Proceedings of USENIX SECURITY 2023. USENIX, August 2023.


Modern video encoding standards such as H.264 are a marvel of hidden complexity. But with hidden complexity comes hidden security risk. Decoding video in practice means interacting with dedicated hardware accelerators and the proprietary, privileged software components used to drive them. The video decoder ecosystem is obscure, opaque, diverse, highly privileged, largely untested, and highly exposed—a dangerous combination.

We introduce and evaluate H26Forge, domain-specific infrastructure for analyzing, generating, and manipulating syn- tactically correct but semantically spec-non-compliant video files. Using H26Forge, we uncover insecurity in depth across the video decoder ecosystem, including kernel memory corruption bugs in iOS, memory corruption bugs in Firefox and VLC for Windows, and video accelerator and application processor kernel memory bugs in multiple Android devices.



  author =       {Willy R. Vasquez and Stephen Checkoway and Hovav Shacham},
  title =        {The Most Dangerous Codec in the World: Finding and
                  Exploiting Vulnerabilities in H.264 Decoders},
  booktitle =    {Proceedings of the USENIX Security Symposium 2023,
  editor =       {Joe Calandrino and Carmela Troncoso},
  year =         2023,
  month =        aug,
  organization = {USENIX},
  url =          {},