CVE-2021-27104
Accellion FTA contains an OS command injection vulnerability exploited via a crafted POST request to various admin endpoints.
Browse: All 2021 CVEs · All vendors
- CISA KEV
- Yes — actively exploited (added 2021-11-03, remediation due 2021-11-17)
- Ransomware
- Known ransomware campaign use
- Weakness (CWE)
- CWE-20, CWE-78
Description
Accellion FTA contains an OS command injection vulnerability exploited via a crafted POST request to various admin endpoints.
Affected products
- Accellion FTA
Affected ranges per NVD CPE data; confirm exact versions in the vendor advisory.
Required action (CISA)
Apply updates per vendor instructions. Federal remediation deadline: 2021-11-17.
How to prioritize this
This vulnerability is on the CISA KEV list, meaning it is being actively exploited — treat it as urgent regardless of the raw CVSS number. Use the live CVE lookup for the latest NVD data, and the CVSS 3.1 calculator to model your own environmental score.
FAQ
Is CVE-2021-27104 actively exploited?
Yes. CISA added CVE-2021-27104 to its Known Exploited Vulnerabilities (KEV) catalog on 2021-11-03, with a federal remediation deadline of 2021-11-17. A KEV listing means real-world exploitation is confirmed, so patching this should be prioritized above many higher-CVSS bugs that aren't being exploited.
What is the CVSS score of CVE-2021-27104?
CVE-2021-27104 has no published CVSS base score yet — NVD analysis can lag disclosure. Check the vendor references for an interim severity.
Related vulnerabilities
- CVE-2021-27102 — Accellion FTA
- CVE-2021-27101 — Accellion FTA
- CVE-2021-27103 — Accellion FTA
- CVE-2019-1068 — Microsoft SQL Server
- CVE-2026-12569 — PTC Windchill and FlexPLM
- CVE-2026-34910 — Ubiquiti UniFi OS
Data source: NVD & CISA KEV. Shown as-is; nothing added. Last generated from NVD data — re-check the live tool for updates.
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