Vulnerability · Published Apr 6, 2026 · Assigned by redhat

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

Medium 5.6

In plain English

A medium-severity out-of-bounds read in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities).

Severity (CVSS 3.1)5.6Medium
Exploit odds (30 days)0.2%top 92.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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 packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:12libtheorano fix listedDEBIAN-CVE-2026-5673
Debian:13libtheorano fix listedDEBIAN-CVE-2026-5673
Debian:14libtheorano fix listedDEBIAN-CVE-2026-5673
Ubuntu:22.04:LTSascno fix listedUBUNTU-CVE-2026-5673
Ubuntu:24.04:LTSascno fix listedUBUNTU-CVE-2026-5673
Ubuntu:25.10ascno fix listedUBUNTU-CVE-2026-5673
Ubuntu:26.04:LTSascno fix listedUBUNTU-CVE-2026-5673
Ubuntu:26.10ascno fix listedUBUNTU-CVE-2026-5673
Ubuntu:22.04:LTSmkvtoolnixno fix listedUBUNTU-CVE-2026-5673
Ubuntu:24.04:LTSmkvtoolnixno fix listedUBUNTU-CVE-2026-5673
Ubuntu:25.10mkvtoolnixno fix listedUBUNTU-CVE-2026-5673
Ubuntu:26.04:LTSmkvtoolnixno fix listedUBUNTU-CVE-2026-5673
Ubuntu:26.10mkvtoolnixno fix listedUBUNTU-CVE-2026-5673
Ubuntu:22.04:LTSogmripno fix listedUBUNTU-CVE-2026-5673
Ubuntu:25.10ogmripno fix listedUBUNTU-CVE-2026-5673
Ubuntu:26.04:LTSogmripno fix listedUBUNTU-CVE-2026-5673
Ubuntu:26.10ogmripno fix listedUBUNTU-CVE-2026-5673

Affected products (as reported)

Weakness: CWE-125 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:H

References