CVE:CVE-2021-3618
CNNVD:CNNVD-202107-216
F5 Nginx是美国F5公司的一款轻量级Web服务器/反向代理服务器及电子邮件（IMAP/POP3）代理服务器，在BSD-like协议下发行。
F5 Nginx存在信任管理问题漏洞，该漏洞源于存在 ALPACA（应用层协议内容混淆）攻击，这会破坏TLS的身份验证，并且可能会发生跨协议攻击。
solution:Upgrade f5 nginx to a higher version than 1.21.0,and avoid the version (,1.21.0); Upgrade sendmail sendmail to a higher version than 8.17,and avoid the version (,8.17); Upgrade vsftpd_project vsftpd to a higher version than 3.0.4,and avoid the version (,3.0.4); Upgrade fedoraproject fedora to a higher version than 33,34,35,and avoid the version 33,34,35; Upgrade debian debian_linux to a higher version than 10.0,and avoid the version 10.0