Usermin / mailbox/detach.cgi eating up all available RAM

Howdy -- this morning, I woke up to all the RAM being used up in the server.

After killing some processes, I discovered a hungry looking Usermin process -- there were three instances of "/usr/share/usermin/mailbox/detach.cgi" running, each using a lot of the CPU, and all using over 600MB of RAM:

1064     27965 16.8  1.5 760344 25796 ?        D    09:19   0:55 /usr/share/usermin/mailbox/detach.cgi
1064     28030 18.2  2.7 850480 44892 ?        D    09:19   0:57 /usr/share/usermin/mailbox/detach.cgi
1064     28088  2.7 29.0 657988 481260 ?      D    09:19   0:08 /usr/share/usermin/mailbox/detach.cgi

I haven't been able to determine what the user was doing yet, though that program appears to be called for reading attachments.

Is it possible to prevent those from running away with so much memory? :-)



Wow, that is excessive - do you happen to know how large the email or attachment that the user was trying to view was?

I've been fighting all day to get that very information, it's harder to get that out of people than you'd think! :-)

After some prodding, it would seem that the attachment was approximately 60MB (yikes!).

The message body itself was tiny, but it was a large (err, "huge") attachment.

What happened is that this user had added this 60MB Excel attachment to an outgoing message in Usermin.

Upon discovering that no one received it, she went into the Sent folder in Usermin, and began attempting to modify the attachment. I think it went downhill from there :-)

Do you have a suggestion on how to prevent users from adding attachments that large?

You can limit the max attachment size at Webmin -> Usermin Configuration -> Usermin Module Configuration -> Read Mail -> Other settings and restrictions -> Maximum total attachments size.

Thanks -- what format is the input expected in? For example, what would I enter there if I wanted the max attachment size to be 10MB?

It is in bytes, sorry ..