CVE-2026-45551: Intermesh Groupoffice

Medium severity, CVSS 5.1. EPSS: 0.4% chance of exploitation in the next 30 days.

Group-Office is an enterprise customer relationship management and groupware tool. Prior to 26.0.25, 25.0.100, and 6.8.165, GroupOffice allows authenticated users to persist arbitrary legacy settings for any user_id via index.php?r=core/saveSetting. A separate client-side sink in the email module injects the email_font_size setting directly into JavaScript without escaping. By combining these two issues, any low-privileged authenticated user can overwrite an administrator's email_font_size setting with a JavaScript payload and trigger stored XSS in the administrator's browser when the GroupOffice web client loads views/Extjs3/modulescripts.php. This vulnerability is fixed in 26.0.25, 25.0.100, and 6.8.165.

Affected products

• Intermesh Groupoffice: from 26.0.1, before 26.0.25 (fixed in 26.0.25); from 25.0.1, before 25.0.1005 (fixed in 25.0.1005); before 6.8.165 (fixed in 6.8.165)

Published 2026-05-29. Last modified 2026-07-21.