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.
Conclusion & alert: CVE-2026-27947 is rated Moderate Risk (46.8/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.10%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-03-21 | 0.30% | 0.10% | -0.20% |
| 2 | 2026-02-28 | — | 0.30% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.4 | 4.0 | CRITICAL |
|
— | — | [email protected] |
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| intermesh | group-office | < 6.8.154 | cpe:2.3:a:intermesh:group-office:*:*:*:*:*:*:*:* |
| intermesh | group-office | >= 25.0.1, < 25.0.87 | cpe:2.3:a:intermesh:group-office:*:*:*:*:*:*:*:* |
| intermesh | group-office | >= 26.0.1, < 26.0.9 | cpe:2.3:a:intermesh:group-office:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://github.com/Intermesh/groupoffice/security/advisories/GHSA-2rwh-9qp7-f92x | Vendor Advisory |