Reference page — cumulative record through Tuesday, October 6, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2026-59927
lepture mistune — Mistune directives/include: mutual `.. include::` recursion crashes the renderer with `RecursionError`, denial of service via two attacker-controlled markdown files
AV AC PR UI S C I A CVSS EPSS %ile KEV
N L N N U N N L 5.3 .0053 42.8 —
AFFECTED
Product Versions Fixed
mistune < 3.3.0 – —
TIMELINE
Jul 7 Reserved by GitHub_M
Jul 8 EXPLOIT PUBLISHED — CVE-2026-59927 (lepture mistune). Public exploit reference added.
Jul 8 Published (CNA: GitHub_M)
Description
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 each other to trigger unbounded recursion, raise RecursionError, and crash the rendering request. This issue is fixed in version 3.3.0.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
|---|
| July 7, 2026 | Reserved | Reserved by GitHub_M |
| July 8, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-59927 (lepture mistune). Public exploit reference added. |
| July 8, 2026 | Published | Published (CNA: GitHub_M) |
Affected
Affected products and packages — 1 row
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|
| lepture | mistune | — | < 3.3.0 | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-59927 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Tuesday, October 6, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
