7.4
HIGH CVSS 3.1
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 :

April 15, 2026, 7:16 p.m.

Remotely Exploit :

Yes !
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.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Apply the latest security patch to enable rate limiting for 2FA verification.
  • 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
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:

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.

  • 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
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.