CVE-2026-3659

What is known

The WP Circliful plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'id' shortcode attribute of the [circliful] shortcode and via multiple shortcode attributes of the [circliful_direct] shortcode in all versions up to and including 1.2. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes. Specifically, in the circliful_shortcode() function, the 'id' attribute value is concatenated directly into an HTML id attribute (line 285) without any escaping, allowing an attacker to break out of the double-quoted attribute and inject arbitrary HTML event handlers. Similarly, the circliful_direct_shortcode() function (line 257) outputs all shortcode attributes directly into HTML data-* attributes without escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Business impact

Successful exploitation of CVE-2026-3659, a medium vulnerability (CVSS 6.4) 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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