filename.xml.pdf - Allowlisted, Bad content [SOLVED]

[SelfMan]

Hi guys,
our eFa 4.0.4 with MailScanner v5.5.1 is blocking file attachments with double extension ".xml.pdf" even though I modified the filename.rules.conf to allow it using:
allow \.xml\.pdf - -

The message details say:
Blocked File: Y
SPAM Allowlisted: Y

Any hints/ideas why that is?
Thanks

[_M_P]

Hi,
maybe

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# allow XMLs converted to PDFs
allow<tab>\.xml\.pdf$<tab>-allow XMLs converted to PDFs<tab>-

is better?

Best regards

[SelfMan]

thanks for the reply _M_P,
I copy/pasted one of the original lines so the tab-formatted content was there the whole time.
I just didn't use the </> code formatting here in the forum. (in hinesight, I should have)
And I also did restart the MailScanner.

[_M_P]

...ok for tabs (are there!), but with a closer look, you'll notice that my RegEx is not the same of your (you missed a $)...

Kind regards

[SelfMan]

Ah, apologies! Brain fart! oh no Eyefart or something dumb.
Thanks for your patience.

efa-file-filter.png (12.31 KiB) Viewed 955 times

I've re-formated a couple lines that were added over time but the e-mails are still being filtered.
"The following e-mails were found to have: Bad Filename Detected"

[_M_P]

Hi,
I'd try a

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mailscanner --lint

...

Best regards

[SelfMan]

I've run the --lint test which found couple other entries with syntax errors that I fixed. (yeah, there were still spaces instead of tabs)
They are now fixed and there are no errors reported. Yet, the pdf file I renames to file.xml.pdf is still filtered out:

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"The following e-mails were found to have: Bad Filename Detected"
"Report: MailScanner: Attempt to hide real filename extension (file.xml.pdf)"

And it ended up in the quarantine.

I've also tried to add the entry to "filetype.rules.conf", but it had no effect.

[SelfMan]

Ok, I found the "issue".
The sequence of rules is important.

The general rule for double extensions MUST be last in the sequence of rules.

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# Deny all other double file extensions. This catches any hidden filenames.
deny	\.[a-z][a-z0-9]{2,3}\s*\.[a-z0-9]{3}$	Found possible filename hiding				Attempt to hide real filename extension

When I moved the rule, all started to work.