CVE-2025-59934 Formbricks missing JWT signature verification
Attackers can bypass authentication and reset passwords by crafting unsigned JWTs due to missing signature verification in Formbricks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-59934?
CVE-2025-59934 is a critical authentication bypass vulnerability in formbricks, published on 26 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Formbricks is an open source qualtrics alternative. Prior to version 4.0.1, Formbricks is missing JWT signature verification. This vulnerability stems from a token validation routine that only decodes JWTs (jwt.decode) without verifying their signatures. Both the email verification token login path and the password reset server action use the same validator, which does not check the token’s signature, expiration, issuer, or audience. If an attacker learns the victim’s actual user.id, they can craft an arbitrary JWT with an alg: "none" header and use it to authenticate and reset the victim’s password. This issue has been patched in version 4.0.1.
Which versions are affected by CVE-2025-59934?
How do I fix CVE-2025-59934?
No fix has been published for CVE-2025-59934 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2025-59934 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-59934 exists.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-7229-q9pv-j6p4.