Resource exhaustion in Lepture Mistune
CVE-2026-49851
Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, Mistune is vulnerable to a CPU exhaustion DoS due to superlinear (approximately O(n²)) behavior in parse_link_text. When parsing Markdown containing many conse…
Vulnerability class: DoS (Denial of Service)
EPSS: 0.003 (27.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Lepture Mistune — versions < 3.3.0
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-49851?
- CVE-2026-49851 is a high-severity vulnerability in Lepture Mistune, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-06-24.
- How severe is CVE-2026-49851?
- High severity. CVSS v3 base score is 7.5 out of 10.