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.
History

Wed, 15 Apr 2026 21:30:00 +0000

Type Values Removed Values Added
First Time appeared Opf
Opf openproject
Vendors & Products Opf
Opf openproject

Wed, 15 Apr 2026 20:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Wed, 15 Apr 2026 19:00:00 +0000

Type Values Removed Values Added
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.
Title OpenProject: 2FA OTP Verification Missing Rate Limiting
Weaknesses CWE-307
References
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-15T20:00:14.503Z

Reserved: 2026-03-23T15:23:42.220Z

Link: CVE-2026-33667

cve-icon Vulnrichment

Updated: 2026-04-15T20:00:04.898Z

cve-icon NVD

Status : Received

Published: 2026-04-15T19:16:35.603

Modified: 2026-04-15T19:16:35.603

Link: CVE-2026-33667

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-04-15T21:15:13Z