DEBIAN-CVE-2026-44898
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.2.1, render_toc_ul() builds a table-of-contents tree from a list of (level, id, text) tuples. Both the id value (used as href="#") and the text value (used as the visible link label) are inserted into tags via a plain Python format string — with no HTML escaping applied to either value. When heading IDs are derived from user-supplied heading text (the standard use-case for readable slug anchors), an attacker can craft a heading whose text breaks out of the href="#..." attribute context, injecting arbitrary HTML tags including
DEBIAN-CVE-2026-44898
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:DEBIAN-CVE-2026-44898
mistune
Source reference: /affected/0/package/name
- Affected versions
- 2.0.4-1
Source reference:
/affected/0/versions2.0.4-2Source reference:
/affected/0/versions3.0.2-1Source reference:
/affected/0/versions3.0.2-2Source reference:
/affected/0/versions3.1.3-1Source reference:
/affected/0/versions3.1.4-1Source reference:
/affected/0/versions3.3.4-1Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
mistune
Source reference: /affected/1/package/name
- Affected versions
- 3.1.3-1
Source reference:
/affected/1/versions3.1.4-1Source reference:
/affected/1/versions3.3.4-1Source reference:
/affected/1/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
mistune
Source reference: /affected/2/package/name
- Affected versions
- 3.1.3-1
Source reference:
/affected/2/versions3.1.4-1Source reference:
/affected/2/versions3.3.4-1Source reference:
/affected/2/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "mistune",
"purl": "pkg:deb/debian/mistune?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"2.0.4-1",
"2.0.4-2",
"3.0.2-1",
"3.0.2-2",
"3.1.3-1",
"3.1.4-1",
"3.3.4-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-44898.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "mistune",
"purl": "pkg:deb/debian/mistune?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"3.1.3-1",
"3.1.4-1",
"3.3.4-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-44898.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "mistune",
"purl": "pkg:deb/debian/mistune?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"3.1.3-1",
"3.1.4-1",
"3.3.4-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-44898.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #56512 · Revision 1
- Added to Heist Feed
- Publisher date