CVE-2026-27947CWE-434CWE-88

Group-Office Vulnerable to Remote Code Execution (RCE)

Critical · published February 27, 2026

CVSS v4.0
9.4
EPSS
1%
Percentile
64.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
9.4 · CRITICAL
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
EPSS
0.01061 · 64.3th percentile
Weaknesses
CWE-434 · Unrestricted Upload of File with Dangerous Type; CWE-88 · Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')
Published
2026-02-27T19:52Z
EPSS history
Timeline
  • 27 FEB 19:52Z
    Group-Office Vulnerable to Remote Code Execution (RCE)
    cvelistv5