CVE-2026-0549 is a stored cross-site scripting vulnerability in the itthinx Groups WordPress plugin (versions up to 3.10.0). The issue stems from improper neutralization of input in the 'groups_group_info' shortcode, where user-supplied attributes are not adequately sanitized or escaped before being rendered on web pages. Authenticated attackers with contributor-level permissions or higher can exploit this to inject arbitrary JavaScript code that executes in the context of users visiting the compromised pages. This vulnerability can lead to limited confidentiality and integrity impacts but does not affect availability.

Successful exploitation allows an authenticated contributor or higher to inject persistent malicious scripts into pages using the vulnerable shortcode. These scripts execute in the browsers of users who view the injected pages, potentially leading to information disclosure or manipulation of user interactions. The CVSS vector indicates network attack vector, low attack complexity, privileges required at the contributor level, no user interaction needed, and impacts on confidentiality and integrity but not availability. No known active exploitation has been reported.

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 and consider disabling or removing the 'groups_group_info' shortcode if feasible. Monitor official itthinx communications for updates and apply any forthcoming patches promptly.