CVE-2021-27104: Accellion FTA OS Command Injection Vulnerability

Critical severity, CVSS 9.8. Actively exploited: in CISA KEV since 2021-11-03. EPSS: 56.7% chance of exploitation in the next 30 days.

Accellion FTA 9_12_370 and earlier is affected by OS command execution via a crafted POST request to various admin endpoints. The fixed version is FTA_9_12_380 and later.

Affected products

• Accellion FTA: up to and including 9_12_370

Published 2021-02-16. Last modified 2026-06-17.