# 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.

- **Severity:** Critical 9.4 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 26 Sep 2025
- **Updated:** 29 Sep 2025
- **Also known as:** GHSA-7229-q9pv-j6p4

## 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.

Weakness: CWE-347 (Improper Verification of Cryptographic Signature), CWE-345 (Insufficient Verification of Data Authenticity), CWE-287 (Improper Authentication)

## 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.

## 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:

- cve-2025-59934 PoC (github_poc): https://github.com/suriryuk/cve-2025-59934

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-59934 and fix it if it is affected.

What it is: 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.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-59934 exists.

Affected product: formbricks. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-59934/ (Markdown: https://insights.sbomify.com/CVE-2025-59934/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-59934
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-59934
- OSV: https://osv.dev/vulnerability/CVE-2025-59934

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-59934/
Summaries are generated and may contain mistakes; the official description above is the record.