CVE-2021-47865
highpriority · track · 0EPSS 0.006 · 48 %ileDEEUEPSS · scored 2026-10-28
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-0189ProFTPD: Schwachstelle ermöglicht Denial of ServiceDeutsch2026-01-21csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in ProFTPD ausnutzen, um einen Denial of Service Angriff durchzuführen.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (13)
External citations — patches, advisories, analysis.
- http://www.proftpd.org/cnnvd
- https://access.redhat.com/security/cve/cve-2021-47865cnnvd
- https://github.com/proftpd/proftpdcnnvd
- https://www.exploit-db.com/exploits/49697cnnvd
- https://www.vulncheck.com/advisories/proftpd-a-remote-denial-of-servicecnnvd
- http://www.proftpd.org/enisa_euvd
- https://github.com/proftpd/proftpd/issues/1298enisa_euvd
- https://www.exploit-db.com/exploits/49697enisa_euvd
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