CVE-2024-56431: libtheora Invalid Negative Shift Vulnerability (Cross-platform)

Memory Corruption Risk in Theora Video Codec (≤ v1.0 7180717)

📢 Advisory Summary

Vulnerability Type: Integer Underflow → Memory Corruption (CWE-191)

Affected Component: libtheora (Theora video codec)

Impacted Versions: ≤ 1.0 (commit 7180717)

CVSSv3 Score: 7.8 (High) [AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H]

Attack Vector: Malicious video file processing

💥 Potential Impact

Successful exploitation could lead to:
✓ Arbitrary code execution in media players
✓ Application crashes (DoS)
✓ Heap memory corruption

🛡️ Mitigation Steps

Immediate Action:

Upgrade to patched libtheora versions (if available)

Recompile with -fno-strict-overflow flag

Detection:

strings /usr/lib/libtheora.so | grep "THEORA 1.0"  

Workarounds:

Disable Theora decoding in affected applications

Sandbox media processing (Firejail/Flatpak)

⚙️ Technical Details

Root Cause: Invalid left shift operation in motion vector processing

Trigger: Specially crafted .ogv/.ogg files

Platforms: All systems using unpatched libtheora

📌 Vendor/Community Response

Patch Status: Under investigation (check Xiph.org

🔍 References

MITRE CVE Entry

OSS-Fuzz Report *

Xiph Security Policy

#CodecSecurity #MemorySafety #CVE202456431 #MultimediaSecurity