RUSTSEC-2025-0008: Openh264 Decoding Functions Heap Overflow Vulnerability

What to do

1. See which version you have: cargo tree -i openh264-sys2 (it also shows which of your dependencies pulls it in).
2. Update within your version requirement: cargo update -p openh264-sys2. If the fix is a newer major or minor than your requirement allows, raise it in Cargo.toml (for example openh264-sys2 = "0.8.0") or update the dependency that pulls it in.
3. Check again with cargo audit, or paste your Cargo.lock into our Cargo.toml checker.

Details from the advisory

OpenH264 recently reported a heap overflow that was fixed in upstream 63db555 and integrated into our 0.6.6 release. For users relying on Cisco's pre-compiled DLL, we also published 0.8.0, which is compatible with their latest fixed DLL version 2.6.0.

In other words:

• if you rely on our source feature only, >=0.6.6 should be safe,
• if you rely on libloading, you must upgrade to 0.8.0 _and_ use their latest DLL >=2.6.0.

Users handling untrusted video files should update immediately.

References

• Package: crates.io/crates/openh264-sys2
• Advisory: rustsec.org/advisories/RUSTSEC-2025-0008.html
• Web: github.com/cisco/openh264/pull/3818/

From the RustSec Advisory Database (CC0-1.0) via the OSV export, downloaded Oct 24, 2026. Severity score computed from the published CVSS vector.