High
libtheora — security advisory
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.
- Products
- libtheora
- Affected versions
- 1.1.1+dfsg.1-16.1, 1.1.1+dfsg.1-16.1+deb12u1, 1.1.1+dfsg.1-17, 1.2.0+dfsg-1, 1.2.0+dfsg-2, 1.2.0+dfsg-3, 1.2.0+dfsg-4, 1.2.0+dfsg-5, 1.2.0+dfsg-6, 1.2.0~alpha1+dfsg-1, 1.2.0~alpha1+dfsg-2, 1.2.0~alpha1+dfsg-3, 1.2.0~alpha1+dfsg-4, 1.2.0~alpha1+dfsg-5, 1.2.0~alpha1+dfsg-6
- Fixed versions
- Not specified
- CVEs
- CVE-2026-5673
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 17:48 UTC · Revision 2
Source evidence
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.
osv:DEBIAN-CVE-2026-5673
libtheora
Fixed versions: Not specified
libtheora
Fixed versions: Not specified
libtheora
Fixed versions: Not specified
Complete source record
{
"id": "9c170ad7efc8132f8b0e091453522c2c561aa9fd6d13340057cacebd7cf5ef6c",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-5673",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-5673",
"summary": "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.",
"evidence": "osv:DEBIAN-CVE-2026-5673",
"products": [
{
"name": {
"value": "libtheora",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.1.1+dfsg.1-16.1",
"evidence": "/affected/0/versions"
},
{
"value": "1.1.1+dfsg.1-16.1+deb12u1",
"evidence": "/affected/0/versions"
},
{
"value": "1.1.1+dfsg.1-17",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0+dfsg-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0+dfsg-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0+dfsg-3",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0+dfsg-4",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0+dfsg-5",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0+dfsg-6",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0~alpha1+dfsg-1",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0~alpha1+dfsg-2",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0~alpha1+dfsg-3",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0~alpha1+dfsg-4",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0~alpha1+dfsg-5",
"evidence": "/affected/0/versions"
},
{
"value": "1.2.0~alpha1+dfsg-6",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "libtheora",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.2.0+dfsg-1",
"evidence": "/affected/1/versions"
},
{
"value": "1.2.0+dfsg-2",
"evidence": "/affected/1/versions"
},
{
"value": "1.2.0+dfsg-3",
"evidence": "/affected/1/versions"
},
{
"value": "1.2.0+dfsg-4",
"evidence": "/affected/1/versions"
},
{
"value": "1.2.0+dfsg-5",
"evidence": "/affected/1/versions"
},
{
"value": "1.2.0+dfsg-6",
"evidence": "/affected/1/versions"
},
{
"value": "1.2.0~alpha1+dfsg-6",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "libtheora",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "1.2.0+dfsg-1",
"evidence": "/affected/2/versions"
},
{
"value": "1.2.0+dfsg-2",
"evidence": "/affected/2/versions"
},
{
"value": "1.2.0+dfsg-3",
"evidence": "/affected/2/versions"
},
{
"value": "1.2.0+dfsg-4",
"evidence": "/affected/2/versions"
},
{
"value": "1.2.0+dfsg-5",
"evidence": "/affected/2/versions"
},
{
"value": "1.2.0+dfsg-6",
"evidence": "/affected/2/versions"
},
{
"value": "1.2.0~alpha1+dfsg-6",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-5673",
"aliases": [
"DEBIAN-CVE-2026-5673"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "libtheora",
"purl": "pkg:deb/debian/libtheora?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"1.1.1+dfsg.1-16.1",
"1.1.1+dfsg.1-16.1+deb12u1",
"1.1.1+dfsg.1-17",
"1.2.0+dfsg-1",
"1.2.0+dfsg-2",
"1.2.0+dfsg-3",
"1.2.0+dfsg-4",
"1.2.0+dfsg-5",
"1.2.0+dfsg-6",
"1.2.0~alpha1+dfsg-1",
"1.2.0~alpha1+dfsg-2",
"1.2.0~alpha1+dfsg-3",
"1.2.0~alpha1+dfsg-4",
"1.2.0~alpha1+dfsg-5",
"1.2.0~alpha1+dfsg-6"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-5673.json"
},
"ecosystem_specific": {
"urgency": "unimportant"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "libtheora",
"purl": "pkg:deb/debian/libtheora?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1.2.0+dfsg-1",
"1.2.0+dfsg-2",
"1.2.0+dfsg-3",
"1.2.0+dfsg-4",
"1.2.0+dfsg-5",
"1.2.0+dfsg-6",
"1.2.0~alpha1+dfsg-6"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-5673.json"
},
"ecosystem_specific": {
"urgency": "unimportant"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "libtheora",
"purl": "pkg:deb/debian/libtheora?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1.2.0+dfsg-1",
"1.2.0+dfsg-2",
"1.2.0+dfsg-3",
"1.2.0+dfsg-4",
"1.2.0+dfsg-5",
"1.2.0+dfsg-6",
"1.2.0~alpha1+dfsg-6"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-5673.json"
},
"ecosystem_specific": {
"urgency": "unimportant"
}
}
],
"modified": "2026-10-27T09:47:34.460969936Z",
"provider": "osv",
"upstream": [
"CVE-2026-5673"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-5673"
]
},
"related_cves": [
{
"value": "CVE-2026-5673",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 461264,
"published_at": "2026-04-06T10:16:03.4+00:00"
}