CVE-2026-2433

What is known

The RSS Aggregator – RSS Import, News Feeds, Feed to Post, and Autoblogging plugin for WordPress is vulnerable to DOM-Based Cross-Site Scripting via postMessage in all versions up to, and including, 5.0.11. This is due to the plugin's admin-shell.js registering a global message event listener without origin validation (missing event.origin check) and directly passing user-controlled URLs to window.open() without URL scheme validation. This makes it possible for unauthenticated attackers to execute arbitrary JavaScript in the context of an authenticated administrator's session by tricking them into visiting a malicious website that sends crafted postMessage payloads to the plugin's admin page.

Business impact

Successful exploitation of CVE-2026-2433, a medium vulnerability (CVSS 6.1) affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

• NVD
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