Manual:$wgApplyIpBlocksToXff

Access: $wgApplyIpBlocksToXff
Apply IP address blocks also to users having a blocked IP in their XFF header.
Introduced in version:1.22.0 (Gerrit change 56715; git #d99bda6e)
Removed in version:still in use
Allowed values:(boolean)
Default value:false

Details edit

When it's set to true, IP address blocks apply also to users having a blocked IP in their XFF header (X-Forwarded-For).

Useful when dealing with vandals making use of well-behaving proxies.