# CVE-2026-33667: OpenProject: 2FA OTP Verification Missing Rate Limiting

> Attackers can bypass two-factor authentication by brute-forcing OTP codes due to missing rate limiting, leading to account takeover.

- **Severity:** High 7.4 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Apr 2026
- **Updated:** 15 Apr 2026

## What is CVE-2026-33667?

CVE-2026-33667 is a high-severity vulnerability in opf openproject, published on 15 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### 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.

Weakness: CWE-307 (Improper Restriction of Excessive Authentication Attempts)

## Which versions are affected by CVE-2026-33667?

It affects 1 product.


Products: Openproject Openproject.

## How do I fix CVE-2026-33667?

No fix has been published for CVE-2026-33667 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-33667 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33667 exists.

## Other vulnerabilities in opf openproject

- [CVE-2026-34717](https://insights.sbomify.com/CVE-2026-34717/): OpenProject: SQL Injection in Cost Reporting =n Operator via parse_number_string (critical 9.9)
- [CVE-2026-25763](https://insights.sbomify.com/CVE-2026-25763/): Command Injection on OpenProject repositories leads to Remote Code Execution (critical 9.4)
- [CVE-2026-24685](https://insights.sbomify.com/CVE-2026-24685/): OpenProject has Argument Injection on Repository module that allows Arbitrary File Write (critical 9.4)
- [CVE-2026-32698](https://insights.sbomify.com/CVE-2026-32698/): OpenProject has a SQL Injection via Custom Field Name that can be chained to Remote Code Execution (critical 9.1)
- [CVE-2026-32703](https://insights.sbomify.com/CVE-2026-32703/): OpenProject's repository files are served with the MIME type allowing them to be used to bypass Content Security Policy (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33667 and fix it if it is affected.

What it is: CVE-2026-33667 is a high-severity vulnerability in opf openproject, published on 15 Apr 2026. 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-2026-33667 exists.

Affected product: opf openproject. 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-2026-33667/ (Markdown: https://insights.sbomify.com/CVE-2026-33667/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33667
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33667
- OSV: https://osv.dev/vulnerability/CVE-2026-33667

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33667/
Summaries are generated and may contain mistakes; the official description above is the record.