hbs vulnerable to XSS via registerAsyncHelper output-escaping bypass
hbs is an Express view engine that wraps Handlebars. Its registerAsyncHelper API bypasses Handlebars' automatic HTML escaping: an async helper returns an opaque placeholder during the first render pass, so the double-brace expression escapes only the placeholder, and after rendering hbs substitutes the placeholder with…
Severity high: primary CNA CVSS 8.1 v3.1 (worst CNA-provided scenario) Not listed in this KEV snapshot. Forecast present in this snapshot.
Published 2026-08-25T10:00:09.678Z. Updated 2026-08-25T19:47:42.474Z.