CVE-2026-115348
Mistune before 3.3.0 Quadratic-Time DoS via parse_link_text
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-400 |
| Vendor | lepture |
| Product | mistune |
| Published | Oct 22, 2026 |
Stay Ahead of the Next One
Get instant alerts for lepture mistune
Be the first to know when new high vulnerabilities affecting lepture mistune are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
lepture / mistune
3.0.0 < 3.3.0
References
Credits
🔍 seankohjs