CVE-2026-34838
Group-Office, a customer relationship management tool, has a critical flaw that lets an authenticated user inject malicious data into settings, enabling them to write files and run arbitrary code on the server. The issue is fixed in versions 6.8.156, 25.0.90, and 26.0.12. Users should update promptly.
An official fix is available, so this entry is kept for 30 days and then removed automatically.
Who is affected
Intermesh Group-Office, versions prior to 6.8.156, 25.0.90, and 26.0.12.
Real-world impact
An attacker who can log in can write files and execute code on the server, potentially taking full control of the system.
Why this severity
The CVSS score of 9.9 reflects that the flaw can be exploited over the network with low effort, requires only low privileges, and gives an attacker full control over confidentiality, integrity, and availability.
What to do about it
- 01Upgrade Group-Office to at least version 6.8.156, 25.0.90, or 26.0.12.
NVD-referenced vendor advisory
Timeline
- Apr 2, 2026 · Apr 2, 2026PublishedDisclosed and added to the National Vulnerability Database.
- Jul 24, 2026 · 11d agoAdvisory updatedThe NVD record was last revised.
- Jul 26, 2026 · 10d agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.
How it’s attacked
References & advisories
- github.com/Intermesh/groupoffice/relea…release notes
- github.com/Intermesh/groupoffice/relea…release notes
- github.com/Intermesh/groupoffice/relea…release notes
- github.com/Intermesh/groupoffice/secur…vendor advisory