Happy DOM: SSRF via iframe and link stylesheet when parsing untrusted HTML
High-risk advisory
CVE-2026-118660
Summary
Happy DOM: SSRF via iframe and link stylesheet when parsing untrusted HTML
Why it matters
GitHub has published a reviewed security advisory for happy-dom. Prioritize it with other application dependency updates, especially because EPSS places it in the 35% percentile.
Operator check
Check whether happy-dom is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available. EPSS probability: 0.4%; percentile: 35%.
Sources
PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.