CVE-2026-33667
OpenProject: 2FA OTP Verification Missing Rate Limiting
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.
INFO
Published Date :
April 15, 2026, 7:16 p.m.
Last Modified :
Oct. 26, 2026, 10:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-33667
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update OpenProject to version 17.3.0 or later.
- Apply vendor-supplied security patches promptly.
- Enable and configure rate limiting for 2FA.
- Monitor failed login attempts.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-33667.
| URL | Resource |
|---|---|
| https://github.com/opf/openproject/security/advisories/GHSA-234r-45m2-w6cv | Exploit Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-33667 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-33667
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-33667 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-33667 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Oct. 26, 2026
Action Type Old Value New Value Added Translation Title: openproject de opf, Description: OpenProject es una aplicación de gestión de proyectos de código abierto. En versiones anteriores a la 17.3.0, la verificación OTP de 2FA en la acción confirm_otp del módulo two_factor_authentication no tiene limitación de velocidad, mecanismo de bloqueo ni seguimiento de intentos fallidos. La configuración existente brute_force_block_after_failed_logins solo cuenta los fallos de inicio de sesión por contraseña y no se aplica a la etapa de verificación de 2FA, y ni los métodos fail_login ni stage_failure incrementan ningún contador, bloquean la cuenta o añaden ningún retraso. Con la ventana de deriva TOTP predeterminada de ±60 segundos que permite aproximadamente 5 códigos válidos en cualquier momento, un atacante que conoce la contraseña de un usuario puede forzar por fuerza bruta el código TOTP de 6 dígitos a aproximadamente 5-10 intentos por segundo con un tiempo de finalización esperado de aproximadamente 11 horas. La misma vulnerabilidad se aplica a la verificación de códigos de respaldo. Esto permite efectivamente la omisión completa de 2FA para cualquier cuenta donde la contraseña sea conocida. Este problema ha sido solucionado en la versión 17.3.0. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'opf', 'product': 'openproject', 'versions': [{'status': 'affected', 'version': '< 17.3.0'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-33667', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-04-15T19:59:53.990177Z'} -
Initial Analysis by [email protected]
Apr. 28, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:openproject:openproject:*:*:*:*:*:*:*:* versions up to (excluding) 17.3.0 Added Reference Type GitHub, Inc.: https://github.com/opf/openproject/security/advisories/GHSA-234r-45m2-w6cv Types: Exploit, Mitigation, Vendor Advisory -
New CVE Received by [email protected]
Apr. 15, 2026
Action Type Old Value New Value 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. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-307 Added Reference https://github.com/opf/openproject/security/advisories/GHSA-234r-45m2-w6cv