Authentication Bypass Vulnerability in Clean Login WordPress Plugin
CVE-2026-90977

5.3MEDIUM

Key Information:

Vendor

WordPress
Status
Clean Login
Vendor
CVE Published:
18 September 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-90977?

The Clean Login WordPress plugin prior to version 1.19 suffers from an authentication bypass vulnerability due to inadequate verification of the registration CAPTCHA. When the session value is empty, unauthorized users can exploit this flaw to bypass the anti-automation controls on the registration form, allowing them to create accounts without completing the CAPTCHA challenge. This issue raises significant concerns about the integrity of user account registrations and the potential for abuse.

Affected Version(s)

Clean Login 0 < 1.19

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-90977 - Proof of Concept

References

https://wpscan.com/vulnerability/368db83e-ed7b-4f67-99db-...
exploitvdb-entrytechnical-description

CVSS V3.1

Score:
5.3
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Arthur Morgan
WPScan
.