oc_huff_tree_unpack in huffdec.c in libtheora in Theora through 1.0 7180717 has an invalid negative left shift. NOTE: this is disputed by third parties because there is no evidence of a security impact, e.g., an application would not crash.
https://www.openwall.com/lists/oss-security/2025/04/25/6
https://github.com/xiph/theora/issues/17#issuecomment-2480630603
https://github.com/xiph/theora/blob/7180717276af1ebc7da15c83162d6c5d6203aabf/lib/huffdec.c#L193
https://github.com/UnionTech-Software/libtheora-CVE-2024-56431-PoC