The ftp client in GNU Inetutils before 2.2 does not validate addresses returned by PASV/LSPV responses to make sure they match the server address. This is similar to CVE-2020-8284 for curl. CREATE(Triage):(User=admin) [CVE-2021-40491|https://nvd.nist.gov/vuln/detail/CVE-2021-40491]
