NAME

FromNameSpoof - perform various tests to detect spoof attempts using the From header name section

SYNOPSIS

loadplugin Mail::SpamAssassin::Plugin::FromNameSpoof

# Does the From:name look like it contains an email address
header   __PLUGIN_FROMNAME_EMAIL  eval:check_fromname_contains_email()

# Is the From:name different to the From:addr header
header   __PLUGIN_FROMNAME_DIFFERENT  eval:check_fromname_different()

# From:name and From:addr owners differ
header   __PLUGIN_FROMNAME_OWNERS_DIFFER  eval:check_fromname_owners_differ()

# From:name domain differs to from header
header   __PLUGIN_FROMNAME_DOMAIN_DIFFER  eval:check_fromname_domain_differ()

# From:name and From:address don't match and owners differ
header   __PLUGIN_FROMNAME_SPOOF  eval:check_fromname_spoof()
 
# From:name address matches To:address
header __PLUGIN_FROMNAME_EQUALS_TO  eval:check_fromname_equals_to()

DESCRIPTION

Perform various tests against From:name header to detect spoofing. Steps in place to ensure minimal FPs.

CONFIGURATION

The plugin allows you to skip emails that have been DKIM signed by specific senders:

fns_ignore_dkim googlegroups.com

FromNameSpoof allows for a configurable closeness when matching the From:addr and From:name, the closeness can be adjusted with:

fns_extrachars 50

Note that FromNameSpoof detects the "owner" of a domain by the following search:

<owner>.<tld>

By default FromNameSpoof will ignore the TLD when testing if From:addr is spoofed. Default 1

fns_check 1

Check levels:

0 - Strict checking of From:name != From:addr
1 - Allow for different tlds
2 - Allow for different aliases but same domain

TAGS

The following tags are added to the set if a spoof is detected. They are available for use in reports, header fields, other plugins, etc.:

_FNSFNAMEADDR_
  Detected spoof address from From:name header

_FNSFNAMEDOMAIN_
  Detected spoof domain from From:name header

_FNSFNAMEOWNER_
  Detected spoof owner from From:name header

_FNSFADDRADDR_
  Actual From:addr address

_FNSFADDRDOMAIN_ 
  Actual From:addr domain

_FNSFADDROWNER_
  Actual From:addr detected owner

EXAMPLE

header __PLUGIN_FROMNAME_SPOOF eval:check_fromname_spoof() header __PLUGIN_FROMNAME_EQUALS_TO eval:check_fromname_equals_to()

meta FROMNAME_SPOOF_EQUALS_TO (__PLUGIN_FROMNAME_SPOOF && __PLUGIN_FROMNAME_EQUALS_TO) describe FROMNAME_SPOOF_EQUALS_TO From:name is spoof to look like To: address score FROMNAME_SPOOF_EQUALS_TO 1.2