CVE-2026-34838Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`

Description

Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.156, 25.0.90, and 26.0.12, a vulnerability in the AbstractSettingsCollection model leads to insecure deserialization when these settings are loaded. By injecting a serialized FileCookieJar object into a setting string, an authenticated attacker can achieve Arbitrary File Write, leading directly to Remote Code Execution (RCE) on the server. This issue has been patched in versions 6.8.156, 25.0.90, and 26.0.12.

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

References and patches

• https://github.com/Intermesh/groupoffice/security/advisories/GHSA-h22j-frrf-5vxq Vendor Advisory
• https://github.com/Intermesh/groupoffice/releases/tag/v25.0.90 Release Notes
• https://github.com/Intermesh/groupoffice/releases/tag/v26.0.12 Release Notes
• https://github.com/Intermesh/groupoffice/releases/tag/v6.8.156 Release Notes