CVE-2026-8883

What is known

The Global Body Mass Index Calculator plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'gbmicalc' shortcode in versions up to, and including, 1.2. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes in the GBMI_Calc_Widget::widget() function. Shortcode attributes are extracted directly into local variables via @extract($args) and then echoed unescaped into an HTML style attribute (height/width) and HTML body context (title), allowing attribute-breakout payloads. 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-2026-8883, 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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