The everviz plugin for WordPress suffers from a stored cross-site scripting vulnerability due to improper neutralization of input during web page generation. The plugin fails to properly sanitize or escape the 'type' and 'hash' shortcode attributes when constructing a <div> element, allowing authenticated users with contributor or higher privileges to inject malicious scripts. These scripts execute in the context of any user viewing the compromised page, potentially leading to information disclosure or session hijacking. The vulnerability affects versions up to and including 1.1 and has a CVSS 3.1 base score of 6.4 (medium severity). There is no vendor advisory or patch information provided at this time.

An attacker with contributor-level or higher access can inject persistent malicious scripts into pages via the everviz shortcode attributes. These scripts execute in the browsers of users who visit the infected pages, potentially leading to theft of user credentials, session tokens, or other sensitive information. The vulnerability does not impact availability and requires authenticated access, limiting the attack surface to users with elevated privileges.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict contributor-level access to trusted users only and consider disabling or removing the everviz plugin if possible to prevent exploitation.