Vulnerability details
CVE-2021-47865
ProFTPD ProFTPD
ProFTPD 1.3.7a - Remote Denial of Service
CVSS 4.0
8.7High
Official 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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 8.7High | 4.0 | CVEProject cvelistV5 (CNA) (VulnCheck) | 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 |
| 7.5High | 3.1 | CVEProject cvelistV5 (CNA) (VulnCheck) | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| ProFTPD | ProFTPD | 1.3.7a | CVEProject cvelistV5 (CNA) |
References and advisories
4- https://www.exploit-db.com/exploits/49697 exploit
- http://www.proftpd.org/ product
- https://github.com/proftpd/proftpd/issues/1298 issue-tracking
- https://www.vulncheck.com/advisories/proftpd-a-remote-denial-of-service third-party-advisory
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Details
- Published
- 2026-01-21
- Last updated
- 2026-04-07
- State
- Published
- Assigner (CNA)
- VulnCheck
Exploit prediction (EPSS)
0.59%
Probability of exploitation in 30 days
48.7%
Percentile (among all CVEs)
SSVC assessment (CISA)
- Automatable
- Yes
- Exploitation
- Proof of concept
- Technical impact
- Partial
Weaknesses (CWE)
- CWE-770Allocation of Resources Without Limits or Throttling