CVE-2021-47865

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
http://www.proftpd.org/
https://github.com/proftpd/proftpd/issues/1298
https://www.exploit-db.com/exploits/49697
https://www.vulncheck.com/advisories/proftpd-a-remote-denial-of-service

Configurations

No configuration.

History

23 Jan 2026, 19:15

Type	Values Removed	Values Added
References	~~{'url': 'https://github.com/proftpd/proftpd', 'source': 'disclosure@vulncheck.com'}~~	() https://github.com/proftpd/proftpd/issues/1298 -

21 Jan 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-21 18:16

Updated : 2026-01-26 15:04

NVD link : CVE-2021-47865

Mitre link : CVE-2021-47865

CVE.ORG link : CVE-2021-47865

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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