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wordfence / plugin · wp-simple-firewall

Shield: Blocks Bots, Protects Users, and Prevents Security Breaches

wp-simple-firewall
total installs
40,000
total vulns
4
critical
0
high
0
medium
4
low
0
latest vuln
patched
4
unpatched
0
avg time to patch
vulnerabilities (4)
Shield Security <= 21.0.8 - Cross-Site Request Forgery to SQL Injection
medium ✓ patched
cvss score 6.5
cwe CWE-89: Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
published Feb 18, 2026
The Shield Security plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 21.0.8. This is due to the plugin allowing nonce verification to be bypassed via user-supplied parameter in the 'isNonceVerifyRequired' function. This makes it possible for unauthenticated attackers to execute SQL injection attacks, extracting sensitive information from the database, via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
Shield Security <= 21.0.8 - Unauthenticated Reflected Cross-Site Scripting via 'message' Parameter
medium ✓ patched
cvss score 6.1
cwe CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
published Feb 18, 2026
The Shield Security plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'message' parameter in all versions up to, and including, 21.0.8 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
Shield Security: Blocks Bots, Protects Users, and Prevents Security Breaches <= 21.0.9 - Missing Authorization to Authenticated (Subscriber+) Email MFA Update
medium ✓ patched
cvss score 4.3
cwe CWE-862: Missing Authorization
published Feb 18, 2026
The Shield Security: Blocks Bots, Protects Users, and Prevents Security Breaches plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `MfaEmailDisable` action in all versions up to, and including, 21.0.9. This makes it possible for authenticated attackers, with Subscriber-level access and above, to disable the global Email 2FA setting for the entire site.
Shield Security <= 21.0.9 - Authenticated (Subscriber+) Insecure Direct Object Reference to Disable Google Authenticator
medium ✓ patched
cvss score 4.3
cwe CWE-639: Authorization Bypass Through User-Controlled Key
published Jan 15, 2026
The Shield: Blocks Bots, Protects Users, and Prevents Security Breaches plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 21.0.9 via the MfaGoogleAuthToggle class due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with Subscriber-level access and above, to disable Google Authenticator for any user.