I finally got so sick of receiving spam from Salesforce that I decided to make an IPTables rule list to block all of Salesforce’s address space from my mail server.
########################
## Block ALL Salesforce IPs ##
## Last Update: 05/12/2024 ##
##############################
#
# ARIN
-A INPUT -s 3.146.43.224/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.56.32.176/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.58.135.64/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.108.0.0/14 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 34.211.108.32/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 34.226.36.48/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 35.182.14.32/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 66.231.80.0/20 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 68.232.192.0/20 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 96.43.144.0/20 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 128.17.0.0/16 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 128.245.0.0/16 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 136.146.0.0/15 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 198.245.80.0/20 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 199.122.120.0/21 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 204.14.232.0/21 -j REJECT –reject-with icmp-port-unreachable
# RIPE
-A INPUT -s 13.36.84.96/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.37.59.29/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.50.12.176/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 15.236.110.244/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 15.236.160.173/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 16.63.106.240/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 18.102.214.64/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 34.253.190.64/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 35.158.127.48/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 35.176.92.16/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 51.17.195.96/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 51.112.11.192/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 85.222.128.0/19 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 159.92.128.0/17 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 160.8.0.0/16 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 161.71.0.0/17 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 163.76.128.0/17 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 163.79.128.0/17 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 185.79.140.0/22 -j REJECT –reject-with icmp-port-unreachable
# APNIC
-A INPUT -s 13.113.196.48/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.124.145.0/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.126.23.64/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.210.3.208/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.215.171.240/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.228.64.80/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.250.175.171/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 13.251.9.241/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 16.78.19.16/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 18.181.43.11/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 35.73.89.117/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 43.201.151.176/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 54.95.206.252/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 54.254.118.123/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 101.53.160.0/19 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 104.161.128.0/17 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 161.32.64.0/18 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 161.32.128.0/17 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 161.71.128.0/17 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 182.50.76.0/22 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 202.129.242.0/23 -j REJECT –reject-with icmp-port-unreachable
# LACNIC
-A INPUT -s 18.228.66.156/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 18.228.207.180/32 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 54.233.205.0/28 -j REJECT –reject-with icmp-port-unreachable
-A INPUT -s 177.71.229.247/32 -j REJECT –reject-with icmp-port-unreachable
Published here in case anyone else wants to use it.