CVE-2026-118694: high-severity vulnerability in trentm python-markdown2
python-markdown2 through 2.5.5 Denial of Service via Unclosed Inline Link Destinations
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.7epss 0.5%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
trentm · python-markdown2References
https://github.com/trentm/python-markdown2https://github.com/trentm/python-markdown2/blob/2.5.5/lib/markdown2.py#L1478-L1492https://github.com/trentm/python-markdown2/blob/2.5.5/lib/markdown2.py#L3029https://github.com/trentm/python-markdown2/issues/750https://github.com/trentm/python-markdown2/pull/751https://www.vulncheck.com/advisories/python-markdown2-through-2.5.5-denial-of-service-via-unclosed-inline-link-destinations