CVE-2026-124307 Fraunhofer HHI VVdeC before 3.2.1 Heap Use-After-Free via ALF APS Redefinition

Medium 5.8 Published 7 Nov 2026 Updated 9 Nov 2026

Exploited in the wild: Not known
Fix: None listed

What is CVE-2026-124307?

CVE-2026-124307 is a medium-severity vulnerability in fraunhoferhhi vvdec, published on 7 Nov 2026.

Official description

Fraunhofer HHI VVdeC before 3.2.1 contains a heap use-after-free vulnerability that allows attackers to corrupt memory by redefining an ALF adaptation parameter set id still referenced by slices. Attackers can supply a crafted VVC bitstream that, with multithreaded decoding, makes worker threads dereference freed APS objects in CABACReader::readAlf() and AdaptiveLoopFilter::reconstructCoeff(), causing crashes or heap corruption.

Weakness: CWE-416

Which versions are affected by CVE-2026-124307?

How do I fix CVE-2026-124307?

No fix has been published for CVE-2026-124307 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-124307 being exploited?

There is no known exploitation of CVE-2026-124307 in the wild and no public exploit code.

Sources

Also known as GHSA-crhc-4fp3-m233.