SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2021-27103

Accellion FTA Server-Side Request Forgery (SSRF) Vulnerability

KEVCRITICAL 9.8EPSS 11.4%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 17 November 2021). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

Accellion FTA 9_12_411 and earlier is affected by SSRF via a crafted POST request to wmProgressstat.html. The fixed version is FTA_9_12_416 and later.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
11.41% probability · 96th percentile
Public exploits
None in Exploit-DB
CISA KEV
Listed 3 November 2021 · due 17 November 2021 · used in ransomware campaigns
Weakness
CWE-918
Affected
accellion/fta
Source
cve@mitre.org
EPSS trend
0%8%15%26 October 2026: 11.41%26 October 202626 October 2026

EPSS 11.4% since 26 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2021-27103

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.