Vulnerability · Published Apr 15, 2026 · Assigned by GitHub_M
CVE-2026-33667OpenProject: 2FA OTP Verification Missing Rate Limiting
High 7.4
In plain English
A high-severity security flaw in openproject from opf. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities).
Official description
OpenProject is an open-source project management application. In versions prior to 17.3.0, 2FA OTP verification in the confirm_otp action of the two_factor_authentication module has no rate limiting, lockout mechanism, or failed-attempt tracking. The existing brute_force_block_after_failed_logins setting only counts password login failures and does not apply to the 2FA verification stage, and neither the fail_login nor stage_failure methods increment any counter, lock the account, or add any delay. With the default TOTP drift window of ±60 seconds allowing approximately 5 valid codes at any time, an attacker who knows a user's password can brute-force the 6-digit TOTP code at roughly 5-10 attempts per second with an expected completion time of approximately 11 hours. The same vulnerability applies to backup code verification. This effectively allows complete 2FA bypass for any account where the password is known. This issue has been fixed in version 17.3.0.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| opf | openproject | < 17.3.0 |
Weakness: CWE-307 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
References
- https://github.com/opf/openproject/security/advisories/GHSA-234r-45m2-w6cv x_refsource_CONFIRM