Mail::SpamAssassin::Plugin::FromNameSpoof(3) User Contributed Perl Documentation Mail::SpamAssassin::Plugin::FromNameSpoof(3)

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

loadplugin Mail::SpamAssassin::Plugin::FromNameSpoof

# From:name and From:addr do not match, matching depends on C<fns_check> setting
header  __PLUGIN_FROMNAME_SPOOF  eval:check_fromname_spoof()

# From:name and From:addr do not match (same as above rule and C<fns_check 0>)
header  __PLUGIN_FROMNAME_DIFFERENT  eval:check_fromname_different()
# From:name and From:addr domains differ
header  __PLUGIN_FROMNAME_DOMAIN_DIFFER  eval:check_fromname_domain_differ()
# From:name looks like it contains an email address (not same as From:addr)
header  __PLUGIN_FROMNAME_EMAIL  eval:check_fromname_contains_email()
# From:name matches any To:addr
header  __PLUGIN_FROMNAME_EQUALS_TO  eval:check_fromname_equals_to()
# From:name and From:addr owners differ
header  __PLUGIN_FROMNAME_OWNERS_DIFFER  eval:check_fromname_owners_differ()
# From:name matches Reply-To:addr
header  __PLUGIN_FROMNAME_EQUALS_REPLYTO  eval:check_fromname_equals_replyto()

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

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


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:


By default FromNameSpoof will ignore the TLD when comparing addresses:

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

"Owner" info can also be mapped as aliases with "fns_add_addrlist". For example, to consider "" as "gmail":

fns_add_addrlist (gmail) *

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.:

  Detected spoof address from From:name header
  Detected spoof domain from From:name header
  Detected spoof owner from From:name header
  Actual From:addr address
  Actual From:addr domain
  Actual From:addr owner

header  __PLUGIN_FROMNAME_SPOOF  eval:check_fromname_spoof()
header  __PLUGIN_FROMNAME_EQUALS_TO  eval:check_fromname_equals_to()
describe FROMNAME_SPOOF_EQUALS_TO From:name is spoof to look like To: address
2023-07-26 perl v5.38.0