CVE-2026-84994

published 2026-10-13

CVE-2026-84994: 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…

Priority P3 52 high 8.7 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 E X CR X IR X AR X MAV X MAC X MAT X MPR X MUI X MVC X MVI X MVA X MSC X MSI X MSA X S X AU X R X V X RE X U X

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.

Affected

4 ranges

Vendor	Product	Version range	Fixed in
builder.io	qwik	< 1.20.0	1.20.0
builder.io	qwik	>= 0 < 1.20.0	1.20.0
qwik.dev	core	>= 0 < 2.0.0-beta37	2.0.0-beta37
qwikdev	qwik	< 2.0.0-beta37	2.0.0-beta37

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CWE-248