CVE-2026-56411

mediumCVSS 6.9covered by 1 sourcefirst seen 2026-06-09

CSIRTS triage

What: This vulnerability is an integer overflow in endDoctypeDecl via NOTATION declarations.
Who is affected: Users of libexpat versions before 2.8.2 are affected.
Urgency: Remediation is important due to a medium severity rating.
Action: Upgrade to libexpat version 2.8.2 or later.

AI-assisted analysis generated from the source advisory — verify against the original.

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Low exploitation risk0.11% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all EPSS-scored CVEs.

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