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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-115347— Mistune before 3.3.0 Quadratic Denial of Service via parse_link_text

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 之前的版本在 函数中存在算法复杂度效率低下的漏洞。远程攻击者可以通过提交包含大量未匹配方括号的 Markdown 内容，利用该漏洞引发拒绝服务（DoS）攻击。当攻击者向 提交此类恶意构造的 Markdown 时，会触发重复的前向扫描，导致工作进程停滞数分钟。

CVSS 7.5 · High

Possible ATT&CK Techniques 1 AI

T1499.003 · Application Exhaustion Flood

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-2026-115347

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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 Denial of Service via parse_link_text
Source: CVE Program / CVE List V5
Vulnerability Description
Mistune before 3.3.0 contains an inefficient algorithmic complexity vulnerability in parse_link_text that allows remote attackers to cause denial of service through unbalanced square brackets. Attackers can submit markdown containing long runs of unmatched brackets to mistune.html(), triggering repeated forward scans that stall worker processes for minutes.
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-2026-115347

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-115347

请登录查看更多情报信息。

Vendor Advisories for CVE-2026-115347 (1)

Other References for CVE-2026-115347 (1)

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-2026-115352 7.5 HIGH Mistune before 3.3.0 Quadratic-Time DoS via Unmatched Brackets in Inline Parser
CVE-2026-115348 7.5 HIGH Mistune before 3.3.0 Quadratic-Time DoS 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-2026-115347

No comments yet

Leave a comment