Really Simple Security (Free, Pro, and Pro Multisite) 9.0.0 - 9.1.1.1 - Authentication Bypass
The Really Simple Security (Free, Pro, and Pro Multisite) plugins for WordPress are vulnerable to authentication bypass in versions 9.0.0 to 9.1.1.1. This is due to improper user check error handling in the two-factor REST API actions with the 'check_login_and_get_user' function. This makes it possible for unauthenticated attackers to log in as any existing user on the site, such as an administrator, when the "Two-Factor Authentication" setting is enabled (disabled by default).
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| WordPress plugin | Really Simple Security – Simple and Performant Security (formerly Really Simple SSL) | >= 9.0.0, <= 9.1.1.1 | 9.1.2 |
| WordPress plugin | Really Simple Security Pro | >= 9.0.0, <= 9.1.1.1 | 9.1.2 |
| WordPress plugin | Really Simple Security Pro multisite | >= 9.0.0, <= 9.1.1.1 | 9.1.2 |
References
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Weakness (CWE)
CWE-288- Platform
- WordPress
- Package
Really Simple Security – Simple and Performant Security (formerly Really Simple SSL), Really Simple Security Pro, Really Simple Security Pro multisite- Disclosed
- 14.11.2024
- Updated
- 11.10.2026 10:22
Sources and licenses
Wordfence Intelligence - 7d5d05ad-1a7a-43d2-bbbf-597e975446be - Wordfence Intelligence
Copyright 1999-2026 The MITRE Corporation
Copyright 2012-2026 Defiant Inc.
This record contains material that is subject to copyright
Copyright 1999-2026 The MITRE Corporation
CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.
https://www.cve.org/Legal/TermsOfUseCopyright 2012-2026 Defiant Inc.
Defiant hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute this software vulnerability information. Any copy of the software vulnerability information you make for such purposes is authorized provided that you include a hyperlink to this vulnerability record and reproduce Defiant's copyright designation and this license in any such copy.
https://www.wordfence.com/wordfence-intelligence-terms-and-conditions/Wordfence Intelligence
Wordfence Intelligence - Defiant, Inc. Copyright Defiant, Inc. All rights reserved except as granted below. License grant, section 3.1 of the Wordfence Intelligence Terms and Conditions (January 26, 2026): Subject to this Agreement, Company hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute the Service. Any copy you make for such purposes is authorized provided that you reproduce Company’s copyright designation, this license, and the license of any disclosed Company licensor in any such copy. Full applicable Agreement: https://www.wordfence.com/wordfence-intelligence-terms-and-conditions/
Vulnerability history: Really Simple Security – Simple and Performant Security (formerly Really Simple SSL)
All published vulnerabilities of this package (WordPress plugin), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 13
- First → latest
- 04.2024 09.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 2
- Medium 10
Disclosures per year
- 2024: 2
- 2025: 1
- 2026: 10
-
Really Simple Security (Free, Pro, and Pro Multisite) 9.0.0 - 9.1.1.1 - Authentication Bypass this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.