CVE-2026-45551: Group-Office: Authenticated Stored XSS in Administrator Context via Arbitrary Cross-User Setting Write
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 userid via index.php?r=core/saveSetting. A separate client-side sink in the email module injects the emailfontsize setting directly into JavaScript without escaping. By combining these two issues, any low-privileged authenticated user can overwrite an administrator's emailfontsize 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 Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
GroupOfficeto a version that resolves this vulnerability.Fixed in 26.0.25 - Upgrade
Upgrade
GroupOfficeto a version that resolves this vulnerability.Fixed in 25.0.100 - Upgrade
Upgrade
GroupOfficeto a version that resolves this vulnerability.Fixed in 6.8.165
Event History
Frequently Asked Questions
What is the severity of CVE-2026-45551?
The severity of CVE-2026-45551 is medium with a score of 5.1.
How do I fix CVE-2026-45551?
To fix CVE-2026-45551, upgrade to Group-Office versions 26.0.25, 25.0.100, or 6.8.165 or later.
What type of vulnerability is CVE-2026-45551?
CVE-2026-45551 is an authenticated stored Cross-Site Scripting (XSS) vulnerability.
Who is affected by CVE-2026-45551?
Authenticated users of Group-Office prior to the specified versions are affected by CVE-2026-45551.
What impact does CVE-2026-45551 have?
CVE-2026-45551 allows authenticated users to persist arbitrary settings that can lead to XSS attacks in the administrator context.