CVE-2026-86428
Last modified
CVE-2026-86428 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. commonmark versions from 1.5.0 before 2.10.0 contain a denial of service vulnerability in the AttributesExtension when processing distinctly-named attributes. Attackers can submit Markdown with numerous distinct attribute names to cause quadratic-time attribute merging and filtering, consuming disproportionate CPU resources and preventing legitimate requests from completing.. EPSS estimates a 0.28% chance of exploitation in the next 30 days.
Description
commonmark versions from 1.5.0 before 2.10.0 contain a denial of service vulnerability in the AttributesExtension when processing distinctly-named attributes. Attackers can submit Markdown with numerous distinct attribute names to cause quadratic-time attribute merging and filtering, consuming disproportionate CPU resources and preventing legitimate requests from completing.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| thephpleague | commonmark | >= 1.5.0, < 2.10.0 |
References
Timeline
- Published
- Last Modified
- Status
- Undergoing Analysis
Frequently Asked Questions
What is CVE-2026-86428?
How severe is CVE-2026-86428?
How do I fix CVE-2026-86428?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-86422ImageMagick before 7.1.2-30 contains a time-of-check-time-of…3.3
- CVE-2026-86423ImageMagick before 7.1.2-30 and 6.9.x before 6.9.13-55 conta…3.3
- CVE-2026-86424ImageMagick before 7.1.2-30 and 6.9.13-55 contains a time-of…2.5
- CVE-2026-86425ImageMagick before 7.1.2-30 and 6.9.x before 6.9.13-55 conta…3.3
- CVE-2026-86426LibreNMS before 26.8.0 contains an authentication bypass vul…9.2
- CVE-2026-86427LibreNMS before 26.8.0 contains an argument injection vulner…8.8
- CVE-2026-86429The league/commonmark (thephpleague/commonmark) library in v…7.5
- CVE-2026-8643pip would treat console_scripts and gui_scripts as paths ins…5.5
- CVE-2026-86430league/commonmark versions before 2.9.1 contain multiple den…7.5
- CVE-2026-86431league/commonmark (thephpleague/commonmark) versions >= 2.7.…7.2
- CVE-2026-86432commonmark versions from 2.0.0 before 2.8.4 contain a denial…5.3
- CVE-2026-86433commonmark versions from 1.5.0 before 2.8.4 contain a denial…7.5
Are you affected by CVE-2026-86428?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST