Vulnerabilities

Vulnerability · CVE-2026-84994

Qwik is a performance-focused JavaScript framework.

Published Oct 13, 2026 · catalog updated Oct 15, 2026 · QwikDev

Check if you run it

No confirmed exploitation is on record for CVE-2026-84994. EPSS is 0.52%. Act only if a listed version of QwikDev is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High8.7
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.52%
Remediation
Version ranges on file
Affected products
npm @builder.io · npm @builder.io/qwik · npm @qwik.dev · npm @qwik.dev/core · vendor @builder.io qwik · vendor 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.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • npm @builder.ioversion unspecified
  • npm @builder.io/qwik0 → 1.20.0
  • npm @builder.io/qwik< 1.20.0
  • npm @qwik.devversion unspecified
  • npm @qwik.dev/core0 → 2.0.0-beta37
  • npm @qwik.dev/core< 2.0.0-beta37
  • vendor @builder.io qwikversion unspecified
  • vendor QwikDev qwikversion unspecified

How to fix CVE-2026-84994

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-84994. EPSS is 0.52%. Act only if a listed version of QwikDev is installed.

Which versions are affected?

Compare what you have installed with 0 → 1.20.0, < 1.20.0, 0 → 2.0.0-beta37, < 2.0.0-beta37. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-248. EPSS 0.52%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

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

  3. Oct 15, 2026 · GitHub Advisory Database

    Fix available

    @builder.io/qwik fixed in 1.20.0; @qwik.dev/core fixed in 2.0.0-beta37

  4. Oct 15, 2026 · GitHub Advisory Database

    Fix available

    @builder.io/qwik fixed in 1.20.0

  5. Oct 15, 2026 · GitHub Advisory Database

    Fix available

    @qwik.dev/core fixed in 2.0.0-beta37

  6. Oct 15, 2026 · GitHub Advisory Database

    Updated

    ### Summary A Qwik server in the default configuration can be crashed with one unauthenticated HTTP request. During qwik-json body parsing, does . If is a plain object whose is a QRL for an unregistered symbol, the async QRL rejects, the rejection is orphaned, and Node terminates the process via its default unhandled-rejection policy. ### Impact One unauthenticated request crashes the server. Loop

Sources

  • CIRCL Vulnerability LookupVulnerability recordCVE-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

    vulnerability.circl.lu
  • CVE.orgVulnerability recordCVE-2026-84994

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-84994

    30-day exploitation probability 0.5%

    first.org
  • GitHub Advisory DatabasePackage advisoryGHSA-x586-xvc8-g7q6

    Qwik: Crashing any Qwik Server via Resource thenable

    github.com
  • GitLab Advisory DatabasePackage advisoryCVE-2026-84994

    A Qwik server in the default configuration can be crashed with one unauthenticated HTTP request. During qwik-json body parsing, ResourceSerializer.$fill$ does Promise.resolve(resource._resolved). If _resolved is a plain object whose .then is a QRL for an unregistered symbol, the async QRL rejects, the rejection is orphaned, and Node terminates the process via its default unhandled-rejection policy

    advisories.gitlab.com
  • NIST NVDVulnerability recordCVE-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
  • OpenSSF OSV / OSV ScannerPackage advisoryGHSA-x586-xvc8-g7q6

    Qwik: Crashing any Qwik Server via Resource thenable

    osv.dev

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.