Is CVE-2021-47865 in the CISA KEV catalog?

No. CVE-2021-47865 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-47865?

CVE-2021-47865 has a CVSS v3 base score of 7.5 (HIGH).

What is the EPSS score for CVE-2021-47865?

CVE-2021-47865 has an EPSS score of 0.54% (41th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2021-47865

HIGH

7.5

CVSS v3

NVD

Description

ProFTPD 1.3.7a contains a denial of service vulnerability that allows attackers to overwhelm the server by creating multiple simultaneous FTP connections. Attackers can repeatedly establish connections using threading to exhaust server connection limits and block legitimate user access.

CWE-770

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

0.54%probability of exploitation in 30 days

41stpercentile

Moderate risk: more likely to be exploited than 41% of all known CVEs.

References

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-01-26.