GHSA-xqg6-98cw-gxhq

Suggest an improvement
Source
https://github.com/advisories/GHSA-xqg6-98cw-gxhq
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-xqg6-98cw-gxhq/GHSA-xqg6-98cw-gxhq.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-xqg6-98cw-gxhq
Aliases
Published
2026-02-03T20:49:22Z
Modified
2026-02-04T18:09:26.229679Z
Severity
  • 9.3 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:L CVSS Calculator
Summary
Prototype Pollution via FormData Processing in Qwik City
Details

Summary

A Prototype Pollution vulnerability exists in the formToObj() function within @builder.io/qwik-city middleware. The function processes form field names with dot notation (e.g., user.name) to create nested objects, but fails to sanitize dangerous property names like __proto__, constructor, and prototype. This allows unauthenticated attackers to pollute Object.prototype by sending crafted HTTP POST requests, potentially leading to privilege escalation, authentication bypass, or denial of service.

Impact

An unauthenticated attacker can supply specially crafted form field names that cause formToObj() to write dangerous keys (for example proto, constructor, prototype) into parsed objects. This results in Prototype Pollution of the server process and can cause privilege escalation, auth bypass, denial-of-service, or other global application integrity failures depending on how objects are used.

Database specific
{
    "cwe_ids": [
        "CWE-1321"
    ],
    "github_reviewed_at": "2026-02-03T20:49:22Z",
    "nvd_published_at": "2026-02-03T22:16:30Z",
    "severity": "CRITICAL",
    "github_reviewed": true
}
References

Affected packages

npm / @builder.io/qwik-city

Package

Name
@builder.io/qwik-city
View open source insights on deps.dev
Purl
pkg:npm/%40builder.io/qwik-city

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1.19.0

Database specific

source
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-xqg6-98cw-gxhq/GHSA-xqg6-98cw-gxhq.json"