CVE-2026-84994: high-severity vulnerability in @builder.io qwik
Qwik: Crashing any Qwik Server via Resource thenable
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%
Qwik is a performance-focused JavaScript framework. Prior to @builder.io/qwik 1.20.0 and @qwik.dev/core 2.0.0-beta.37, default server-side qwik-json deserialization causes ResourceSerializer.$fill$ to pass resource._resolved to Promise.resolve without first rejecting attacker-controlled thenables. An unauthenticated request can provide a plain object whose then property is a QRL for an unregistered symbol, causing an orphaned asynchronous rejection that terminates Node.js under its default unhandled-rejection policy. A single request can crash a server, and repeated requests can keep replicas unavailable. This issue is fixed in @builder.io/qwik 1.20.0 and @qwik.dev/core 2.0.0-beta.37.
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
Related CVEs — @builder.io qwik
In the same product, most dangerous first.
CVE-2026-27971CRITICALQwik affected by unauthenticated RCE via server$ DeserializationEPSS 5.5%CVE-2026-25150CRITICALPrototype Pollution via FormData Processing in Qwik CityEPSS 0.7%CVE-2024-41677MEDIUMCross-site Scripting (XSS) vulnerability due to improper HTML escaping in qwikEPSS 0.5%CVE-2026-32701HIGHQwik has array method pollution in FormData processing, allowing type confusion and DoSEPSS 0.4%CVE-2025-53620CRITICALCrashing any Qwik ServerEPSS 0.4%CVE-2026-25148MEDIUMQwik SSR XSS via Unsafe Virtual Node SerializationEPSS 0.3%