CVE-2026-76098

Mistune is a Python Markdown parser with renderers and plugins. Versions 3.3.0 through 3.3.2 are vulnerable to DoS through deeply nested tokens. HTML rendering creates deeply nested emphasis tokens from consecutive asterisk characters, and recursive rendering in HTMLRenderer.render_token() can exceed Python's recursion limit and raise RecursionError, allowing crafted Markdown to crash a parsing process. This issue is fixed in version 3.3.3

Published 24 Aug 2026, 20:17 UTC Last modified 24 Aug 2026, 21:17 UTC

7.5

CVSS 3.1 HIGH base score CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SCX

ShellCodeX risk assessment

High remediation priority based on exploitation evidence, CVSS conditions and affected-product data.

PriorityEvidenceDecision use

High EPSS estimates a 0.30% near-term exploitation probability. Validate against your asset inventory and vendor advisory.

High The vulnerable path is reachable over a network. Validate against your asset inventory and vendor advisory.

High Exploitation does not require prior privileges. Validate against your asset inventory and vendor advisory.

Attack profile

The conditions required to exploit this vulnerability and its potential impact.

Attack vector Network

Attack complexity Low

Privileges required None

User interaction None

Scope Unchanged

Confidentiality None

Integrity None

Availability High

Exploitability3.9

Impact3.6

Affected products

Product applicability statements supplied with the NVD record.

NVD has not published structured affected-product data for this record.

Weakness classification

CWE categories help security teams group the underlying software weakness.

CWECWE-674

Source references

External advisories, patches and technical reports attached to this CVE record.

NVD National Vulnerability Database recordnvd.nist.gov 01 Technical reference security-advisories@github.com 02 Technical reference security-advisories@github.com