MediumFix available
expat — security advisory
libexpat versions 2.7.2 through 2.8.5 contain an integer overflow vulnerability in expat_realloc() function on 32-bit platforms when computing allocation sizes. Attackers supplying malicious XML to applications parsing with vulnerable libexpat can cause heap buffer overflow, memory corruption, or denial of service.
- Products
- expat
- Affected versions
- 2.5.0-1, 2.5.0-1+deb12u1, 2.5.0-1+deb12u2, 2.5.0-1+deb12u3, 2.5.0-1+deb12u4, 2.7.1-2, 2.7.2-1, 2.7.3-1, 2.7.3-2, 2.7.4-1, 2.7.5-1, 2.8.0-1, 2.8.0-2, 2.8.1-1, 2.8.2-1, 2.8.2-1~deb13u1, 2.8.3-1, 2.8.3-1~deb13u1, 2.8.4-1, 2.8.4-2, 2.8.5-1, 2.8.5-2
- Fixed versions
- 2.5.0-1+deb12u5, 2.8.5-2, 2.9.0-1~deb13u1
- CVEs
- CVE-2026-102633
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 17:58 UTC · Revision 1
Source evidence
libexpat versions 2.7.2 through 2.8.5 contain an integer overflow vulnerability in expat_realloc() function on 32-bit platforms when computing allocation sizes. Attackers supplying malicious XML to applications parsing with vulnerable libexpat can cause heap buffer overflow, memory corruption, or denial of service.
osv:DEBIAN-CVE-2026-102633
expat
Fixed versions: 2.5.0-1+deb12u5
expat
Fixed versions: 2.9.0-1~deb13u1
expat
Fixed versions: 2.8.5-2
Complete source record
{
"id": "15eb1dc69420bca1898afd3c7c844cc96471f82d3d62d9feb39ffd49413bdd65",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-102633",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-102633",
"summary": "libexpat versions 2.7.2 through 2.8.5 contain an integer overflow vulnerability in expat_realloc() function on 32-bit platforms when computing allocation sizes. Attackers supplying malicious XML to applications parsing with vulnerable libexpat can cause heap buffer overflow, memory corruption, or denial of service.",
"evidence": "osv:DEBIAN-CVE-2026-102633",
"products": [
{
"name": {
"value": "expat",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.5.0-1+deb12u5",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "2.5.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.5.0-1+deb12u1",
"evidence": "/affected/0/versions"
},
{
"value": "2.5.0-1+deb12u2",
"evidence": "/affected/0/versions"
},
{
"value": "2.5.0-1+deb12u3",
"evidence": "/affected/0/versions"
},
{
"value": "2.5.0-1+deb12u4",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "expat",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.9.0-1~deb13u1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": [
{
"value": "2.7.1-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.7.2-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.7.3-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.7.3-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.7.4-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.7.5-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.0-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.1-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.2-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.2-1~deb13u1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.3-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.3-1~deb13u1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.4-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.4-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.5-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.8.5-2",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "expat",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.8.5-2",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "2.7.1-2",
"evidence": "/affected/2/versions"
},
{
"value": "2.7.2-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.7.3-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.7.3-2",
"evidence": "/affected/2/versions"
},
{
"value": "2.7.4-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.7.5-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.0-2",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.1-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.2-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.2-1~deb13u1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.3-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.3-1~deb13u1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.4-1",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.4-2",
"evidence": "/affected/2/versions"
},
{
"value": "2.8.5-1",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2026-102633",
"aliases": [
"DEBIAN-CVE-2026-102633"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.5.0-1+deb12u5"
}
]
}
],
"package": {
"name": "expat",
"purl": "pkg:deb/debian/expat?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"2.5.0-1",
"2.5.0-1+deb12u1",
"2.5.0-1+deb12u2",
"2.5.0-1+deb12u3",
"2.5.0-1+deb12u4"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-102633.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.9.0-1~deb13u1"
}
]
}
],
"package": {
"name": "expat",
"purl": "pkg:deb/debian/expat?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"2.7.1-2",
"2.7.2-1",
"2.7.3-1",
"2.7.3-2",
"2.7.4-1",
"2.7.5-1",
"2.8.0-1",
"2.8.0-2",
"2.8.1-1",
"2.8.2-1",
"2.8.2-1~deb13u1",
"2.8.3-1",
"2.8.3-1~deb13u1",
"2.8.4-1",
"2.8.4-2",
"2.8.5-1",
"2.8.5-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-102633.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.8.5-2"
}
]
}
],
"package": {
"name": "expat",
"purl": "pkg:deb/debian/expat?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"2.7.1-2",
"2.7.2-1",
"2.7.3-1",
"2.7.3-2",
"2.7.4-1",
"2.7.5-1",
"2.8.0-1",
"2.8.0-2",
"2.8.1-1",
"2.8.2-1",
"2.8.2-1~deb13u1",
"2.8.3-1",
"2.8.3-1~deb13u1",
"2.8.4-1",
"2.8.4-2",
"2.8.5-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-102633.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-22T09:00:05.965530768Z",
"provider": "osv",
"upstream": [
"CVE-2026-102633"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-102633"
]
},
"related_cves": [
{
"value": "CVE-2026-102633",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 405350,
"published_at": "2026-09-29T17:17:06.98+00:00"
}