On Thu, 22 Feb 2018, RW wrote:
On Thu, 22 Feb 2018 15:54:45 +0100
saqariden wrote:
Hello guys,
I have the following SA rule which is supposed to block base64
encoded mails:
This may be dangerous. If someone doesn't wish to use 8bit text then
base64 encoding of UTF-8 is a sensible choice; QP is very inefficient
unless the text is almost completely ASCII.
body EN_BASE64_B /(Content-Transfer-Encoding:
base64\sContent-Type: text\/(plain|html);
charset="?utf-8"?)|(Content-Type: text\/(plain|html);
charset="?utf-8"?\sContent-Transfer-Encoding: base64)/i
describe EN_BASE64_B TEXT OR HTML B64 ENCODED
score EN_BASE64_B 5
this is the mail that i want to stop:
the rule don't match for this mail, but it match when i had an empty
line like this:
..
How can i do to match the both, with the empty line and without it?
body rules check only the text that's visible in a mail client
(including the subject text). This rule only works at all if you make
the mime unparsable.
For mime you need "full" instead of "body". You then need an
explicit \n between lines.
I agree with RW about the risk of FPs from that approach, particularly if you
have international correspondents.
However if you really want to do that, you need to use the "mimeheader" kind of
rule. It works like a regular message 'header' type of rule but processes mime
headers within the message contents.
For example, to catch messages with a particular mime attachment file name I
have a rule:
mimeheader L_BANK_PHISH1 Content-Disposition =~ m!attachment;
filename="[\w\s\d._-]{1,30}verification\.html?"$!i
--
Dave Funk University of Iowa
<dbfunk (at) engineering.uiowa.edu> College of Engineering
319/335-5751 FAX: 319/384-0549 1256 Seamans Center
Sys_admin/Postmaster/cell_admin Iowa City, IA 52242-1527
#include <std_disclaimer.h>
Better is not better, 'standard' is better. B{
