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DEBIAN-CVE-2026-59928

Type: advisorySource: OSV1 source record

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a Markdown document containing many repeated or distinct reference-link definitions causes quadratic work in src/mistune/block_parser.py and the ref_links environment dictionary handling, allowing denial of service through CPU exhaustion. This issue is fixed in version 3.3.0.

Announced Source revision 1
Original source ↗

DEBIAN-CVE-2026-59928

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-2026-59928

mistune

Source reference: /affected/0/package/name

Affected versions
3.1.3-1

Source reference: /affected/0/versions

3.1.4-1

Source reference: /affected/0/versions

3.3.4-1

Source 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/versions

3.1.4-1

Source reference: /affected/1/versions

3.3.4-1

Source reference: /affected/1/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=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-2026-59928.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-2026-59928.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  }
]

Publisher severity

No explicit severity was provided.

Event
#56048 · Revision 1
Added to Heist Feed
Publisher date
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