What’s Vulnerable › Vulnerabilities

CVE-2024-56431

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.8% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2024-12-25 · updated 2026-06-17
• Weakness: CWE-863

Description

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.

Affected products

• Xiph Theora: before 1.2.0 — fixed in 1.2.0

How to fix

Upgrade to a fixed version: Xiph Theora 1.2.0. Check the vendor advisory for mitigations.

References

• https://github.com/UnionTech-Software/libtheora-CVE-2024-56431-PoC
• https://github.com/xiph/theora/blob/7180717276af1ebc7da15c83162d6c5d6203aabf/lib/huffdec.c#L193
• https://github.com/xiph/theora/issues/17#issuecomment-2480630603
• https://www.openwall.com/lists/oss-security/2025/04/25/6
• http://www.openwall.com/lists/oss-security/2025/04/25/4
• http://www.openwall.com/lists/oss-security/2025/04/25/6

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