MediumFix available
lxml — security advisory
An issue was discovered in lxml before 4.2.5. lxml/html/clean.py in the lxml.html.clean module does not remove javascript: URLs that use escaping, allowing a remote attacker to conduct XSS attacks, as demonstrated by "j a v a s c r i p t:" in Internet Explorer. This is a similar issue to CVE-2014-3146.
- Products
- lxml
- Affected versions
- Not specified
- Fixed versions
- 4.2.5-1
- CVEs
- CVE-2018-19787
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 00:29 UTC · Revision 1
Source evidence
An issue was discovered in lxml before 4.2.5. lxml/html/clean.py in the lxml.html.clean module does not remove javascript: URLs that use escaping, allowing a remote attacker to conduct XSS attacks, as demonstrated by "j a v a s c r i p t:" in Internet Explorer. This is a similar issue to CVE-2014-3146.
osv:DEBIAN-CVE-2018-19787
lxml
Fixed versions: 4.2.5-1
lxml
Fixed versions: 4.2.5-1
lxml
Fixed versions: 4.2.5-1
Complete source record
{
"id": "162265271a324605821db4ca79612b018a764bc5c3d0b9e60bda743aed189b2d",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2018-19787",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2018-19787",
"summary": "An issue was discovered in lxml before 4.2.5. lxml/html/clean.py in the lxml.html.clean module does not remove javascript: URLs that use escaping, allowing a remote attacker to conduct XSS attacks, as demonstrated by \"j a v a s c r i p t:\" in Internet Explorer. This is a similar issue to CVE-2014-3146.",
"evidence": "osv:DEBIAN-CVE-2018-19787",
"products": [
{
"name": {
"value": "lxml",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.2.5-1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "lxml",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.2.5-1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "lxml",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.2.5-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
}
],
"severity": "medium",
"structured": {
"id": "DEBIAN-CVE-2018-19787",
"aliases": [
"DEBIAN-CVE-2018-19787"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.2.5-1"
}
]
}
],
"package": {
"name": "lxml",
"purl": "pkg:deb/debian/lxml?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-19787.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.2.5-1"
}
]
}
],
"package": {
"name": "lxml",
"purl": "pkg:deb/debian/lxml?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-19787.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.2.5-1"
}
]
}
],
"package": {
"name": "lxml",
"purl": "pkg:deb/debian/lxml?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2018-19787.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-23T18:03:21.039262086Z",
"provider": "osv",
"upstream": [
"CVE-2018-19787"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2018-19787"
]
},
"related_cves": [
{
"value": "CVE-2018-19787",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 421247,
"published_at": "2018-12-02T10:29:00.227+00:00"
}