CVE-2026-115348

CVSS 8.7 (high) · published 2026-10-22

Mistune from 3.0.0 before 3.3.0 contains an algorithmic complexity vulnerability in the inline link parser's parse_link_text function that allows unauthenticated attackers to exhaust CPU with unbalanced brackets. Attackers can submit Markdown containing many unbalanced '[' or '![' characters, forcing repeated unbounded forward scans and tying up worker processes for minutes.

Weakness: CWE-400

Source: NVD CVE-2026-115348

References

• https://github.com/lepture/mistune/security/advisories/GHSA-x2gr-6qf2-fc9x
• https://www.vulncheck.com/advisories/mistune-before-3.3.0-quadratic-time-dos-via-parse-link-text

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