CVE-2026-34838: 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…

PriorityP272critical9.9CVSS 3.1

AVNACLPRLUINSCCHIHAH

EPSS

1.03%

59.3th percentile

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.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
intermesh	group-office	< 6.8.156	6.8.156
intermesh	group-office	>= 25.0.1 < 25.0.90	25.0.90
intermesh	group-office	>= 26.0.1 < 26.0.12	26.0.12
intermesh	groupoffice	< 6.8.156	6.8.156
intermesh	groupoffice	< 25.0.90	25.0.90
intermesh	groupoffice	< 26.0.12	26.0.12

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