HighFix available
libxfont — security advisory
A heap buffer overflow due to missing size checking in the property buffer when parsing PCF files in libXfont2 ComputeScaledProperties() before libXfont2 before 2.0.8 could be used by attackers using authenticated X clients to execute code within the X server.
- Products
- libxfont
- Affected versions
- 1:2.0.6-1, 1:2.0.6-1+hurd.1, 1:2.0.6-2
- Fixed versions
- 1:2.0.6-1+deb12u1, 1:2.0.6-1+deb13u1, 1:2.0.8-1
- CVEs
- CVE-2026-56003
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 12:22 UTC · Revision 2
Source evidence
A heap buffer overflow due to missing size checking in the property buffer when parsing PCF files in libXfont2 ComputeScaledProperties() before libXfont2 before 2.0.8 could be used by attackers using authenticated X clients to execute code within the X server.
osv:DEBIAN-CVE-2026-56003
libxfont
Fixed versions: 1:2.0.6-1+deb12u1
libxfont
Fixed versions: 1:2.0.6-1+deb13u1
libxfont
Fixed versions: 1:2.0.8-1
Complete source record
{
"id": "e36849386cb5a54a29a01c769356db1b0df41e99157c2a9c5c05d9b9324b3077",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-56003",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-56003",
"summary": "A heap buffer overflow due to missing size checking in the property buffer when parsing PCF files in libXfont2 ComputeScaledProperties() before libXfont2 before 2.0.8 could be used by attackers using authenticated X clients to execute code within the X server.",
"evidence": "osv:DEBIAN-CVE-2026-56003",
"products": [
{
"name": {
"value": "libxfont",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.0.6-1+deb12u1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "1:2.0.6-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "libxfont",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "1:2.0.6-1+deb13u1",
"evidence": "/affected/1/ranges"
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],
"affected_versions": [
{
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"evidence": "/affected/1/versions"
}
]
},
{
"name": {
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"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
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"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
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"value": "1:2.0.6-1",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.0.6-1+hurd.1",
"evidence": "/affected/2/versions"
},
{
"value": "1:2.0.6-2",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-56003",
"aliases": [
"DEBIAN-CVE-2026-56003"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.0.6-1+deb12u1"
}
]
}
],
"package": {
"name": "libxfont",
"purl": "pkg:deb/debian/libxfont?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"1:2.0.6-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-56003.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.0.6-1+deb13u1"
}
]
}
],
"package": {
"name": "libxfont",
"purl": "pkg:deb/debian/libxfont?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"1:2.0.6-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-56003.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "1:2.0.8-1"
}
]
}
],
"package": {
"name": "libxfont",
"purl": "pkg:deb/debian/libxfont?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"1:2.0.6-1",
"1:2.0.6-1+hurd.1",
"1:2.0.6-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-56003.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-26T11:47:37.177979093Z",
"provider": "osv",
"upstream": [
"CVE-2026-56003"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-56003"
]
},
"related_cves": [
{
"value": "CVE-2026-56003",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 450922,
"published_at": "2026-07-08T10:16:23.577+00:00"
}