CVE-2026-118694

EUVD-2026-112495
python-markdown2 through 2.5.5 contains a denial of service vulnerability that allows remote users to exhaust CPU by submitting Markdown with unclosed inline link destinations. Attackers can submit repeated '[a](' or '![a](' sequences, causing _find_balanced to rescan the remaining document for each link and consume quadratic CPU time.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
References
https://github.com/trentm/python-markdown2
https://github.com/trentm/python-markdown2/blob/2.5.5/lib/markdown2.py#L1478-L1492
https://github.com/trentm/python-markdown2/blob/2.5.5/lib/markdown2.py#L3029
https://github.com/trentm/python-markdown2/issues/750
https://github.com/trentm/python-markdown2/pull/751
https://www.vulncheck.com/advisories/python-markdown2-through-2.5.5-denial-of-service-via-unclosed-inline-link-destinations