Findings

CVE-2026-84994

Qwik is a performance-focused JavaScript framework.

Published Oct 13, 2026 · updated Oct 14, 2026 · QwikDev qwik

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.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 13, 2026 · NIST NVD

    Detected

    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 unregistere

  2. Oct 14, 2026 · NIST NVD

    Updated

    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 unregistere

Affected

  • vendor @builder.io qwikversion unspecified
  • vendor QwikDev qwikversion unspecified

Sources

  • 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-con

    vulnerability.circl.lu
  • CVE.orgCVE-2026-84994

    Official CVE identifier

    cve.org
  • FIRST EPSSCVE-2026-84994

    30-day exploitation probability 0.5%

    first.org
  • NIST NVDCVE-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 deserialization causes ResourceSerializer.$fill$ to pass resource._resolved to Promise.resolve without first rejecting attacker-con

    nvd.nist.gov

References

CVE-2026-84994 · ZeroDay Findings