Group-Office is an enterprise customer relationship management and groupware tool. Versions prior to 26.0.9, 25.0.87, and 6.8.154 have an authenticated Remote Code Execution vulnerability in the TNEF attachment processing flow. The vulnerable path extracts attacker-controlled files from `winmail.dat` and then invokes `zip` with a shell wildcard (`*`).
Because extracted filenames are attacker-controlled, they can be interpreted as `zip` options and lead to arbitrary command execution. Versions 26.0.9, 25.0.87, and 6.8.154 fix the issue.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v4.0