CVE-2021-30047

HIGH NUCLEI

vsftpd 3.0.3 - Denial of Service via Connection Limit Exhaustion

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2021-30047. PoCs published by xynmaps. A Nuclei detection template is also available.

AI-analyzed exploit summary This exploit performs a Denial of Service (DoS) attack against vsftpd 3.0.3 by flooding the server with multiple FTP connections, exhausting its connection limit. It uses threading to spawn multiple FTP processes, effectively blocking legitimate users from connecting.

Description

VSFTPD 3.0.3 allows attackers to cause a denial of service due to limited number of connections allowed.

Exploits (1)

exploitdb WORKING POC VERIFIED
by xynmaps · pythonremotemultiple
https://www.exploit-db.com/exploits/49719

This exploit performs a Denial of Service (DoS) attack against vsftpd 3.0.3 by flooding the server with multiple FTP connections, exhausting its connection limit. It uses threading to spawn multiple FTP processes, effectively blocking legitimate users from connecting.

Classification
Working Poc 95%
Attack Type
Dos
Complexity
Trivial
Reliability
Reliable
Target: vsftpd 3.0.3
No auth needed
Prerequisites: Network access to the target vsftpd server · vsftpd server with no connection rate limiting
devstral-2 · analyzed Feb 18, 2026 Full analysis →

Nuclei Templates (1)

vsftpd < 3.0.3 - DoS
HIGHVERIFIEDby pussycat0x
Shodan: vsftpd || product:"vsftpd"

References (1)

Core 1
Core References
Exploit, Third Party Advisory, VDB Entry
https://www.exploit-db.com/exploits/49719

Scores

CVSS v3 7.5
EPSS 0.0307
EPSS Percentile 86.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

Status published
Products (1)
vsftpd_project/vsftpd 3.0.3
Published Aug 22, 2023
Tracked Since Feb 18, 2026