The package github.com/pires/go-proxyproto before 0.6.0 are vulnerable to Denial of Service (DoS) via creating connections without the proxy protocol header.
https://snyk.io/vuln/SNYK-GOLANG-GITHUBCOMPIRESGOPROXYPROTO-1316439
https://github.com/pires/go-proxyproto/releases/tag/v0.6.0
https://github.com/pires/go-proxyproto/pull/74/commits/cdc63867da24fc609b727231f682670d0d1cd346