High severity · published Feb 27, 2026
CVE-2026-27947
Group-Office Vulnerable to Remote Code Execution (RCE)
8.8
CVSS
0.8%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GR
groupoffice · Intermesh
>= 26.0.0, < 26.0.9; >= 25.0.0, < 25.0.87; < 6.8.154 · source: vendor
GR
Group-office · Intermesh
before 6.8.154; 25.0.1 before 25.0.87; 26.0.1 before 26.0.9 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-27947
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-27947
Vendor Advisory
https://github.com/Intermesh/groupoffice/security/advisories/GHSA-2rwh-9qp7-f92x
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