CVE-2025-59934: Auth Bypass (CVSS 9.4)

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.

Is your site exposed to CVE-2025-59934?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

9.4

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L

Weakness Type (CWE)

CWE-287 Improper Authentication

CWE-345 CWE-345

CWE-347 CWE-347

References

Other References

https://github.com/formbricks/formbricks/blob/843110b0d6c37b5c0da54291616f84c91c55c4fc/apps/web/lib/jwt.ts#L114-L117 https://github.com/formbricks/formbricks/commit/eb1349f205189d5b2d4a95ec42245ca98cf68c82 https://github.com/formbricks/formbricks/pull/6596 https://github.com/formbricks/formbricks/security/advisories/GHSA-7229-q9pv-j6p4

Frequently Asked Questions

What is CVE-2025-59934? +

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. It has a CVSS v3.1 base score of 9.4 (CRITICAL).

How severe is CVE-2025-59934? +

CVE-2025-59934 has a CVSS v3.1 score of 9.4 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

How do I check if I'm vulnerable to CVE-2025-59934? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-47202

Kavita is a cross platform reading server. Prior to 0.9.0.2, an Improper Token validation flaw permits a remote and unauthenticated …

CVE-2026-61740

LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.5.4, when LightRAG is deployed with LIGHTRAG_API_KEY set but AUTH_ACCOUNTS unset, …

CVE-2026-47159

Vaultwarden is a Bitwarden-compatible server written in Rust. Prior to 1.36.0, Vaultwarden's SSO discovery and pre-validation flow returned organization-related SSO …

CVE-2026-44720

OpenLearnX is an open-source, decentralized learning and assessment platform. Prior to 2.0.4, a critical authentication vulnerability was identified in OpenLearnX …

CVE-2025-24032

PAM-PKCS#11 is a Linux-PAM login module that allows a X.509 certificate based user login. Prior to version 0.6.13, if cert_policy …

CVE-2024-5174

A flaw in Gliffy results in broken authentication through the reset functionality of the application.

CVE-2025-59934