CVE-2026-8905: OSIRIS8 Osiris Signature Banner

Medium severity, CVSS 6.1. EPSS: 0.2% chance of exploitation in the next 30 days.

The Osiris Signature Banner plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 0.5. This is due to missing or incorrect nonce validation on a function. This makes it possible for unauthenticated attackers to update settings and inject malicious web scripts via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

Affected products

• OSIRIS8 Osiris Signature Banner: up to and including 0.5

Published 2026-06-24. Last modified 2026-06-25.