CVE-2026-86432
commonmark versions from 2.0.0 before 2.8.4 contain a denial of service vulnerability in XmlRenderer that emits depth-proportional indentation for every XML tag. Attackers can provide deeply nested Markdown or AST structures to cause quadratic memory consumption and output amplification, exhausting server resources.
Scoring
- Severity
- MEDIUM
- CVSS base score
- 6.9
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- EPSS probability
- 0.25%
- CWE
- CWE-405
- Published
- 2026-09-07
- Last modified
- 2026-09-07
Affected products
- thephpleague commonmark
- thephpleague commonmark
Weakness type
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