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

Source: https://junglewise.ai/threats/cve-2021-27104-accellion-fta-os-command-injection-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2021-27104 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2021-11-03

Accellion FTA is vulnerable to OS command injection via crafted POST requests to various administrative endpoints. This allows an unauthenticated remote attacker to execute arbitrary commands on the underlying operating system.

Technologies: [Accellion FTA](https://junglewise.ai/threats/technologies/fta). Vendors: [Accellion](https://junglewise.ai/threats/vendors/accellion).

## Quick answers

**Is CVE-2021-27104 exploited in the wild?** Yes. CVE-2021-27104 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2021-27104?** Critical severity, with a CVSS score of 9.8, published 3 November 2021.

**Which products and versions are affected?** Accellion FTA 9_12_370 and earlier.

**Is there a fix for CVE-2021-27104?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2021-27104 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2021-27104?** Check whether you run Accellion FTA. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Accellion FTA 9_12_370 and earlier

## Timeline

- 2021-02-16: disclosed: NVD Published Date
- 2021-11-03: kev added: Date added to CISA Known Exploited Vulnerabilities Catalog
- 2021-11-17: other: CISA KEV due date for remediation

## Related threats

- [Accellion FTA OS Command Injection Vulnerability](https://junglewise.ai/threats/cve-2021-27102-accellion-fta-os-command-injection-vulnerability)
- [Accellion FTA SQL Injection Vulnerability](https://junglewise.ai/threats/cve-2021-27101-accellion-fta-sql-injection-vulnerability)
- [Accellion FTA Server-Side Request Forgery (SSRF) Vulnerability](https://junglewise.ai/threats/cve-2021-27103-accellion-fta-server-side-request-forgery-ssrf-vulnerability)