What is CVE-2026-59927?

CVE-2026-59927 is a medium-severity vulnerability in Lepture Mistune, classified under Uncontrolled Recursion. CVSS score: 5.3/10. Published 2026-07-08.

How severe is CVE-2026-59927?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Lepture Mistune

CVE-2026-59927

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, the Include directive in src/mistune/directives/include.py detects only direct self-includes and not indirect cycles, allowing two markdown files that include…

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

Lepture Mistune — versions < 3.3.0

Weakness classification (CWE)

CWE-674 — Uncontrolled Recursion
CWE-755 — Improper Handling of Exceptional Conditions

References

security-advisories@github.com (x_refsource_CONFIRM)
security-advisories@github.com (x_refsource_MISC)
security-advisories@github.com (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-59927?: CVE-2026-59927 is a medium-severity vulnerability in Lepture Mistune, classified under Uncontrolled Recursion. CVSS score: 5.3/10. Published 2026-07-08.
How severe is CVE-2026-59927?: Medium severity. CVSS v3 base score is 5.3 out of 10.