CVE-2026-124307 PUBLISHED

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.

• Alexander A. Shvedov (sigdevel) finder

• https://github.com/fraunhoferhhi/vvdec/issues/391
• https://github.com/fraunhoferhhi/vvdec/issues/390
• https://github.com/fraunhoferhhi/vvdec/commit/1eddb30c4b8e02f3d13ba24aa7e52f1aa7b08c01
• https://github.com/fraunhoferhhi/vvdec/blob/v3.2.0/source/Lib/CommonLib/Slice.h#L2570
• https://github.com/fraunhoferhhi/vvdec/blob/v3.2.0/source/Lib/CommonLib/ParameterSetManager.h#L97
• https://github.com/fraunhoferhhi/vvdec/blob/v3.2.0/source/Lib/DecoderLib/CABACReader.cpp#L428-L429
• https://github.com/fraunhoferhhi/vvdec
• VulnCheck Advisory: Fraunhofer HHI VVdeC before 3.2.1 Heap Use-After-Free via ALF APS Redefinition

• Use After Free CWE