CVE-2026-34838 (GCVE-0-2026-34838)
Vulnerability from cvelistv5 – Published: 2026-04-02 19:15 – Updated: 2026-04-03 12:55
VLAI
EPSS
VEX
Title
Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`
Summary
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.
Severity
10 (Critical)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-03 12:55 UTC
CWE
- CWE-502 - Deserialization of Untrusted Data
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/Intermesh/groupoffice/security… | x_refsource_CONFIRM |
| https://github.com/Intermesh/groupoffice/releases… | x_refsource_MISC |
| https://github.com/Intermesh/groupoffice/releases… | x_refsource_MISC |
| https://github.com/Intermesh/groupoffice/releases… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Intermesh | groupoffice |
Affected:
< 6.8.156
Affected: < 25.0.90 Affected: < 26.0.12 |
guessed |
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