#language en
== SpamAssassin Rule:  MIME_BASE64_TEXT ==

''Standard description:''   Message text disguised using base64 encoding

=== Explanation ===

The message contains text that has been encoded using Base64 content transfer encoding but does not use a character set known to require it.  This does not apply to text in the UTF-8 or big5 character sets.

This technique is assumed to be used by spammers as a form of obfuscation, presumably to bypass filters that are not MIME-aware.


=== Further Info ===

The default scores for this rule can be found [[http://spamassassin.apache.org/tests.html|in the online list of tests]].

For details on Base64 encoding see [[http://www.apps.ietf.org/rfc/rfc2045.html#sec-6.8|RFC 2045 sec 6.8]]

This rule is known to trigger false positives in some circumstances. See ([[https://issues.apache.org/SpamAssassin/buglist.cgi?quicksearch=MIME_BASE64|buglist]])

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