High
node-markdown-it — security advisory
linkify-it is a links recognition library with full Unicode support. Prior to 5.0.1, LinkifyIt.prototype.match, the package's primary public API, has O(N²) algorithmic complexity for inputs containing many fuzzy links or emails because the JavaScript-level scan loop re-slices input and re-runs unanchored regex searches on progressively shorter tails. Any service that synchronously renders untrusted Markdown with linkify:true on a request hot path can inherit a worker-process denial of service triggerable by a tens-of-KB request body. This issue is fixed in version 5.0.1.
- Products
- node-markdown-it
- Affected versions
- 10.0.0+dfsg-2, 10.0.0+dfsg-3, 10.0.0+dfsg-3.1, 10.0.0+dfsg-4, 10.0.0+dfsg-5, 10.0.0+dfsg-6, 22.2.3+dfsg+~12.2.3-2, 22.2.3+dfsg+~12.2.3-4, 22.2.3+dfsg+~12.2.3-5
- Fixed versions
- Not specified
- CVEs
- CVE-2026-48801
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 03:07 UTC · Revision 1
Source evidence
linkify-it is a links recognition library with full Unicode support. Prior to 5.0.1, LinkifyIt.prototype.match, the package's primary public API, has O(N²) algorithmic complexity for inputs containing many fuzzy links or emails because the JavaScript-level scan loop re-slices input and re-runs unanchored regex searches on progressively shorter tails. Any service that synchronously renders untrusted Markdown with linkify:true on a request hot path can inherit a worker-process denial of service triggerable by a tens-of-KB request body. This issue is fixed in version 5.0.1.
osv:UBUNTU-CVE-2026-48801
node-markdown-it
Fixed versions: Not specified
node-markdown-it
Fixed versions: Not specified
node-markdown-it
Fixed versions: Not specified
node-markdown-it
Fixed versions: Not specified
Complete source record
{
"id": "be52142140cf6853f0f80bb155c4910ce4b51c6286d1991c0599c3216d7bb1bd",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-48801",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-48801",
"summary": "linkify-it is a links recognition library with full Unicode support. Prior to 5.0.1, LinkifyIt.prototype.match, the package's primary public API, has O(N²) algorithmic complexity for inputs containing many fuzzy links or emails because the JavaScript-level scan loop re-slices input and re-runs unanchored regex searches on progressively shorter tails. Any service that synchronously renders untrusted Markdown with linkify:true on a request hot path can inherit a worker-process denial of service triggerable by a tens-of-KB request body. This issue is fixed in version 5.0.1.",
"evidence": "osv:UBUNTU-CVE-2026-48801",
"products": [
{
"name": {
"value": "node-markdown-it",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "10.0.0+dfsg-2",
"evidence": "/affected/0/versions"
},
{
"value": "10.0.0+dfsg-3",
"evidence": "/affected/0/versions"
},
{
"value": "10.0.0+dfsg-3.1",
"evidence": "/affected/0/versions"
},
{
"value": "10.0.0+dfsg-4",
"evidence": "/affected/0/versions"
},
{
"value": "10.0.0+dfsg-5",
"evidence": "/affected/0/versions"
},
{
"value": "10.0.0+dfsg-6",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "node-markdown-it",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "22.2.3+dfsg+~12.2.3-2",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "node-markdown-it",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "22.2.3+dfsg+~12.2.3-4",
"evidence": "/affected/2/versions"
},
{
"value": "22.2.3+dfsg+~12.2.3-5",
"evidence": "/affected/2/versions"
}
]
},
{
"name": {
"value": "node-markdown-it",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "22.2.3+dfsg+~12.2.3-2",
"evidence": "/affected/3/versions"
},
{
"value": "22.2.3+dfsg+~12.2.3-4",
"evidence": "/affected/3/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "UBUNTU-CVE-2026-48801",
"aliases": [
"UBUNTU-CVE-2026-48801"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
},
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
},
{
"type": "Ubuntu",
"score": "medium"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "node-markdown-it",
"purl": "pkg:deb/ubuntu/node-markdown-it?arch=source&distro=jammy",
"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
"10.0.0+dfsg-2",
"10.0.0+dfsg-3",
"10.0.0+dfsg-3.1",
"10.0.0+dfsg-4",
"10.0.0+dfsg-5",
"10.0.0+dfsg-6"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48801.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "node-markdown-it",
"binary_version": "10.0.0+dfsg-6"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "node-markdown-it",
"purl": "pkg:deb/ubuntu/node-markdown-it?arch=source&distro=noble",
"ecosystem": "Ubuntu:24.04:LTS"
},
"versions": [
"22.2.3+dfsg+~12.2.3-2"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48801.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "node-markdown-it",
"binary_version": "22.2.3+dfsg+~12.2.3-2"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "node-markdown-it",
"purl": "pkg:deb/ubuntu/node-markdown-it?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"22.2.3+dfsg+~12.2.3-4",
"22.2.3+dfsg+~12.2.3-5"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48801.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "node-markdown-it",
"binary_version": "22.2.3+dfsg+~12.2.3-5"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "node-markdown-it",
"purl": "pkg:deb/ubuntu/node-markdown-it?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
"22.2.3+dfsg+~12.2.3-2",
"22.2.3+dfsg+~12.2.3-4"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-48801.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "node-markdown-it",
"binary_version": "22.2.3+dfsg+~12.2.3-4"
}
]
}
}
],
"modified": "2026-10-17T13:00:23.478948868Z",
"provider": "osv",
"upstream": [
"CVE-2026-48801"
],
"references": [
"https://ubuntu.com/security/CVE-2026-48801",
"https://www.cve.org/CVERecord?id=CVE-2026-48801",
"https://github.com/markdown-it/linkify-it/commit/6be6d15e0641bf1daeaa977d500cabc743166159",
"https://github.com/markdown-it/linkify-it/security/advisories/GHSA-22p9-wv53-3rq4"
]
},
"related_cves": [
{
"value": "CVE-2026-48801",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 360473,
"published_at": "2026-07-14T21:17:00+00:00"
}