CVE-2021-47865

8.7 highEPSS 0.6%

High (8.7). EPSS 0.6% chance of exploitation in the next 30 days.

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.

Severity

CVSS 4.0

8.7 high

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

7.5 high

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

EPSS: 0.6% chance of exploitation in the next 30 days; higher than 48% of CVEs (scores of 2026-10-31)
CWE: CWE-770
Published: 2026-01-21
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

References

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

Check your stack JSON