Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-115352— Mistune before 3.3.0 Quadratic-Time DoS via Unmatched Brackets in Inline Parser

Quick assessment

Affected
lepture mistune
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Mistune 3.3.0 之前的版本中，内联链接解析器存在算法复杂度漏洞。未认证的攻击者可以通过提交大量未匹配的左方括号（ ）字符，耗尽 CPU 资源。攻击者仅需发送极小的 Markdown 载荷，即可触发 和 函数的 O(N²) 复杂度探测行为，导致渲染工作进程被占用超过 30 秒（每 16 KB 输入数据）。

CVSS 7.5 · High

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service

Affected Version Matrix 2

VendorProduct Version RangeStatus
lepture mistune < 3.3.0 affected
3.3.0 unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-115352

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Mistune before 3.3.0 Quadratic-Time DoS via Unmatched Brackets in Inline Parser
Source: CVE Program / CVE List V5
Vulnerability Description
Mistune before 3.3.0 contains an algorithmic complexity vulnerability in the inline link parser that allows unauthenticated attackers to exhaust CPU by submitting long runs of unmatched '[' characters. Attackers can send small markdown payloads that trigger O(N^2) parse_link_text and parse_link_label probing, occupying rendering workers for 30+ seconds per 16 KB input.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
算法复杂性
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
lepture mistune 0 ~ 3.3.0 -

II. Public POCs for CVE-2026-115352

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-115352

请登录查看更多情报信息。

Vendor Advisories for CVE-2026-115352 (2)

Same Patch Batch · lepture · 2026-10-22 · 9 CVEs total

CVE-2026-115353 8.6 HIGH Mistune before 3.3.0 Path Traversal via include Directive
CVE-2026-115349 7.5 HIGH Mistune 3.0.0 before 3.3.0 Denial of Service via Nested Bracket Parsing
CVE-2026-115348 7.5 HIGH Mistune before 3.3.0 Quadratic-Time DoS via parse_link_text
CVE-2026-115347 7.5 HIGH Mistune before 3.3.0 Quadratic Denial of Service via parse_link_text
CVE-2026-115355 7.5 HIGH Mistune before 3.3.0 Path Traversal and XSS via Include Directive
CVE-2026-115354 6.5 MEDIUM Mistune before 3.3.0 Arbitrary Local File Read via Include Directive
CVE-2026-115350 6.1 MEDIUM Mistune before 3.3.0 Stored XSS via Include Directive HTML Files
CVE-2026-115351 4.7 MEDIUM Mistune 3.2.1 before 3.3.0 CSS Injection via Figure Directive figwidth Option

IV. Related Vulnerabilities

Same product: mistune
Same vendor: lepture
Same weakness: CWE-407

V. Comments for CVE-2026-115352

No comments yet

Leave a comment