Fix CVE(s): CVE-2026-56131, CVE-2026-56407, CVE-2026-56408
* SECURITY UPDATE: - debian/patches/CVE-2026-56131.patch: block unsafe parser APIs from handler callbacks using handler call-depth tracking in expat/lib/xmlparse.c - debian/patches/CVE-2026-56407.patch: prevent signed integer overflow when assigning entity values in expat/lib/xmlparse.c - debian/patches/CVE-2026-56408.patch: prevent integer overflow in copyString() allocation size calculations in expat/lib/xmlparse.c - CVE-2026-56131 - CVE-2026-56407 - CVE-2026-56408
- Products
- expat, libexpat1, libexpat1-dev
- Affected versions
- Not specified
- Fixed versions
- 2.2.9-1ubuntu0.8+tuxcare.els6
- CVEs
- CVE-2026-56131, CVE-2026-56407, CVE-2026-56408
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 10:59 UTC · Revision 1
Source evidence
Fix CVE(s): CVE-2026-56131, CVE-2026-56407, CVE-2026-56408
core-osv · Original sourcePublished 4 Aug 2026, 09:44 UTC
* SECURITY UPDATE: - debian/patches/CVE-2026-56131.patch: block unsafe parser APIs from handler callbacks using handler call-depth tracking in expat/lib/xmlparse.c - debian/patches/CVE-2026-56407.patch: prevent signed integer overflow when assigning entity values in expat/lib/xmlparse.c - debian/patches/CVE-2026-56408.patch: prevent integer overflow in copyString() allocation size calculations in expat/lib/xmlparse.c - CVE-2026-56131 - CVE-2026-56407 - CVE-2026-56408
osv:CLSA-2026-1785836657
expat
Fixed versions: 2.2.9-1ubuntu0.8+tuxcare.els6
libexpat1
Fixed versions: 2.2.9-1ubuntu0.8+tuxcare.els6
libexpat1-dev
Fixed versions: 2.2.9-1ubuntu0.8+tuxcare.els6
Complete source record
{
"id": "29686dd5867c43fe33ac80ba0e8b96bdcf5e248efcfcd0342185aef3e7be3c04",
"url": "https://osv.dev/vulnerability/CLSA-2026-1785836657",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Fix CVE(s): CVE-2026-56131, CVE-2026-56407, CVE-2026-56408",
"summary": "* SECURITY UPDATE: - debian/patches/CVE-2026-56131.patch: block unsafe parser APIs from handler callbacks using handler call-depth tracking in expat/lib/xmlparse.c - debian/patches/CVE-2026-56407.patch: prevent signed integer overflow when assigning entity values in expat/lib/xmlparse.c - debian/patches/CVE-2026-56408.patch: prevent integer overflow in copyString() allocation size calculations in expat/lib/xmlparse.c - CVE-2026-56131 - CVE-2026-56407 - CVE-2026-56408",
"evidence": "osv:CLSA-2026-1785836657",
"products": [
{
"name": {
"value": "expat",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.2.9-1ubuntu0.8+tuxcare.els6",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libexpat1",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.2.9-1ubuntu0.8+tuxcare.els6",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "libexpat1-dev",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "2.2.9-1ubuntu0.8+tuxcare.els6",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "CLSA-2026-1785836657",
"aliases": [
"CLSA-2026-1785836657"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.2.9-1ubuntu0.8+tuxcare.els6"
}
]
}
],
"package": {
"name": "expat",
"purl": "pkg:deb/tuxcare/expat?distro=ubuntu-20.04",
"ecosystem": "TuxCare:Ubuntu:20.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu20.04els/CLSA-2026-1785836657.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.2.9-1ubuntu0.8+tuxcare.els6"
}
]
}
],
"package": {
"name": "libexpat1",
"purl": "pkg:deb/tuxcare/libexpat1?distro=ubuntu-20.04",
"ecosystem": "TuxCare:Ubuntu:20.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu20.04els/CLSA-2026-1785836657.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.2.9-1ubuntu0.8+tuxcare.els6"
}
]
}
],
"package": {
"name": "libexpat1-dev",
"purl": "pkg:deb/tuxcare/libexpat1-dev?distro=ubuntu-20.04",
"ecosystem": "TuxCare:Ubuntu:20.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu20.04els/CLSA-2026-1785836657.json"
}
}
],
"modified": "2026-10-26T09:31:40.140009599Z",
"provider": "osv",
"upstream": [
"CVE-2026-56131",
"CVE-2026-56407",
"CVE-2026-56408"
],
"references": [
"https://errata.tuxcare.com/els_os/ubuntu20.04els/CLSA-2026-1785836657.html",
"https://nvd.nist.gov/vuln/detail/CVE-2026-56131",
"https://nvd.nist.gov/vuln/detail/CVE-2026-56407",
"https://nvd.nist.gov/vuln/detail/CVE-2026-56408"
]
},
"related_cves": [
{
"value": "CVE-2026-56131",
"evidence": "/upstream"
},
{
"value": "CVE-2026-56407",
"evidence": "/upstream"
},
{
"value": "CVE-2026-56408",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 448015,
"published_at": "2026-08-04T09:44:30+00:00"
}