CVE-2026-25150 Prototype Pollution via FormData Processing in Qwik City
Unauthenticated attackers can pollute Object.prototype via crafted form data in Qwik City, potentially leading to privilege escalation or authentication bypass.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-25150?
CVE-2026-25150 is a critical vulnerability in QwikDev qwik, published on 3 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Qwik is a performance focused javascript framework. Prior to version 1.19.0, 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. This issue has been patched in version 1.19.0.
Weakness: CWE-1321
Which versions are affected by CVE-2026-25150?
2 open source packages ship an affected version, including @builder.io/qwik-city. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
@builder.io/qwik-city npm | All versions | 1.19.0 |
@builder.io/qwik-city npm | All versions | 1.19.0 |
Products include Qwik Qwik.
How do I fix CVE-2026-25150?
Upgrade @builder.io/qwik-city to 1.19.0 or later.
Is CVE-2026-25150 being exploited?
There is no known exploitation of CVE-2026-25150 in the wild and no public exploit code.
Other vulnerabilities in QwikDev qwik
- CVE-2023-1283 Code Injection in builderio/qwik
- CVE-2026-27971 Qwik affected by unauthenticated RCE via server$ Deserialization
- CVE-2026-32701 Qwik has array method pollution in FormData processing, allowing type confusion and DoS
- CVE-2024-41677 Cross-site Scripting (XSS) vulnerability due to improper HTML escaping in qwik
- CVE-2023-0410 Cross-site Scripting (XSS) - Generic in builderio/qwik
Sources
Also known as GHSA-xqg6-98cw-gxhq.