The Spectra Gutenberg Blocks plugin for WordPress suffers from a stored XSS vulnerability (CWE-79) due to improper neutralization of input during web page generation. Authenticated attackers with Contributor or higher privileges can inject arbitrary JavaScript into pages via the uagb block. This malicious script executes in the context of users viewing the affected pages, potentially leading to session hijacking or other script-based attacks. The vulnerability affects all versions up to and including 2.19.0. The CVSS 3.1 base score is 6.4, reflecting network attack vector, low attack complexity, and privileges required at the contributor level.

Successful exploitation allows an authenticated user with Contributor-level access or above to inject and store malicious scripts that execute in the browsers of users who visit the infected pages. This can lead to information disclosure, session hijacking, or other client-side attacks. The vulnerability does not impact availability and requires some level of authenticated access, limiting the scope of attackers.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, restrict Contributor-level access to trusted users only. Monitor plugin updates from brainstormforce for a security patch addressing this issue. Avoid using affected versions of the Spectra Gutenberg Blocks plugin in high-risk environments.