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.
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Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
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History
Fri, 26 Sep 2025 23:15:00 +0000
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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. | |
Title | Formbricks missing JWT signature verification | |
Weaknesses | CWE-287 CWE-345 CWE-347 |
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cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2025-09-26T23:03:30.995Z
Reserved: 2025-09-23T14:33:49.505Z
Link: CVE-2025-59934

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Status : Received
Published: 2025-09-26T23:15:32.613
Modified: 2025-09-26T23:15:32.613
Link: CVE-2025-59934

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