CVE-2026-86428
commonmark 1.5.0 before 2.10.0 Denial of Service via Attributes
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-407 |
| Vendor | thephpleague |
| Product | commonmark |
| Published | Sep 7, 2026 |
| Last Updated | Sep 8, 2026 |
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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
thephpleague / commonmark
1.5.0 < 2.10.0
References
Credits
🔍 manus-use