{"id":"CVE-2026-25150","aliases":["GHSA-xqg6-98cw-gxhq"],"url":"https://o3.security/vulnerability/CVE-2026-25150","summary":"Prototype Pollution via FormData Processing in Qwik City","details":"### Summary\n\nA 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.\n\n### Impact\nAn 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.","published":"2026-02-03T21:12:50.417Z","modified":"2026-08-12T03:51:46.042956321Z","cvss":{"score":9.3,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@builder.io/qwik-city","fixedVersion":"1.19.0"}],"fix":{"url":"https://github.com/QwikDev/qwik/commit/5f65bae2bc33e6ca0c21e4cfcf9eae05077716f7","label":"QwikDev/qwik@5f65bae"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25150.json"},{"type":"ADVISORY","url":"https://github.com/QwikDev/qwik/security/advisories/GHSA-xqg6-98cw-gxhq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-25150"},{"type":"FIX","url":"https://github.com/QwikDev/qwik/commit/5f65bae2bc33e6ca0c21e4cfcf9eae05077716f7"},{"type":"PACKAGE","url":"https://github.com/QwikDev/qwik"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:46.042956321Z"}}