What’s Vulnerable › Vulnerabilities

CVE-2026-5673: Libtheora: libtheora: denial of service or information disclosure via malformed avi file processing

• Severity: high (CVSS 7.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-04-06 · updated 2026-10-26
• Weakness: CWE-125

Description

A flaw was found in libtheora. This heap-based out-of-bounds read vulnerability exists within the AVI (Audio Video Interleave) parser, specifically in the avi_parse_input_file() function. A local attacker could exploit this by tricking a user into opening a specially crafted AVI file containing a truncated header sub-chunk. This could lead to a denial-of-service (application crash) or potentially leak sensitive information from the heap.

Affected products

• Red Hat Enterprise Linux: 6.0, 7.0, 8.0, 9.0, 10.0
• Xiph Theora: all versions

References

• https://access.redhat.com/security/cve/CVE-2026-5673
• https://bugzilla.redhat.com/show_bug.cgi?id=2455340
• https://github.com/xiph/theora/issues/24

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