Which ports are considered unsafe by Chrome?

Some ports generate an error (ERR_UNSAFE_PORT) when browsing to them via Chrome (see this related question). Which ports are considered safe, and which are unsafe by default?

3 Answers

The following is a list of all of the restricted ports on Chrome:

1, // tcpmux 7, // echo 9, // discard 11, // systat 13, // daytime 15, // netstat 17, // qotd 19, // chargen 20, // ftp data 21, // ftp access 22, // ssh 23, // telnet 25, // smtp 37, // time 42, // name 43, // nicname 53, // domain 69, // tftp 77, // priv-rjs 79, // finger 87, // ttylink 95, // supdup 101, // hostriame 102, // iso-tsap 103, // gppitnp 104, // acr-nema 109, // pop2 110, // pop3 111, // sunrpc 113, // auth 115, // sftp 117, // uucp-path 119, // nntp 123, // NTP 135, // loc-srv /epmap 137, // netbios 139, // netbios 143, // imap2 161, // snmp 179, // BGP 389, // ldap 427, // SLP (Also used by Apple Filing Protocol) 465, // smtp+ssl 512, // print / exec 513, // login 514, // shell 515, // printer 526, // tempo 530, // courier 531, // chat 532, // netnews 540, // uucp 548, // AFP (Apple Filing Protocol) 554, // rtsp 556, // remotefs 563, // nntp+ssl 587, // smtp (rfc6409) 601, // syslog-conn (rfc3195) 636, // ldap+ssl 993, // ldap+ssl 995, // pop3+ssl 1719, // h323gatestat 1720, // h323hostcall 1723, // pptp 2049, // nfs 3659, // apple-sasl / PasswordServer 4045, // lockd 5060, // sip 5061, // sips 6000, // X11 6566, // sane-port 6665, // Alternate IRC [Apple addition] 6666, // Alternate IRC [Apple addition] 6667, // Standard IRC [Apple addition] 6668, // Alternate IRC [Apple addition] 6669, // Alternate IRC [Apple addition] 6697, // IRC + TLS 10080, // Amanda 

Source: Chrome source.

The reason it's called unsafe is not because it's unsafe to Chrome, it's because it's unsafe to those services, where an attacker may try to use Chrome as a proxy to attacking services on those ports. More explanation here:

by default web services normally run on port 80 and SSL encrypted traffic runs on port 443 so these should be "safe" ports. This is typically known as "default ports" or "well known ports". "safe" seems to be a chrome-ism :)

"safe" is a bit meaningless though. If it runs on anouther port its more likely to be dodgy traffic, but just because its on port 80 dosent mean it wont install malware and etc on your pc.