[ZIMBRA] Prevent User Customizing “FROM” header

Background

Some of our Zimbra customers are complaining for authenticated user can customizing FROM header which can lead to fraud email. this issue can be reproduce by using thunderbird once compose an email as following picture.

customize_from_header.png

or by using this script, change variables username, password, fake_from and to_addr based on your environment.

 

Solution

I created customized milter engine using python milter library for my workaroud with following features:

Continue reading “[ZIMBRA] Prevent User Customizing “FROM” header”

Advertisements

Enhance ClearOS 6 Password Policy

Background

Our customer using ClearOS 6 (professional edition) to store user password and almost all applications using it as external authentication so user only has to remember one password and Zimbra is one of the application.

Recently the public IP that used as mail outgoing traffic being listed in RBL and by our check in server we found there are some user account has been hijacked so it’s sending spam email to outside domain (gmail.com, outlook.com, etc) then i set suspected status to close in zimbra also reset it’s password randomly  but it’s happen quite frequently.

Then i created simple php script using clearOS API to scan weak password (based on list), surprisingly there are bunch of user using weak password such as “Passwd11”, “Paasword88”, etc. so i conclude the builtin password policy in ClearOS is not good enough to prevent it.

Solution

Based on my experience create and modifying ClearOS module (as it’s just a PHP code) i modified ClearOS user module. to increase password policy by following criteria:

  • Maximum length
  • Minimum length
  • Minimum uppercase
  • Minimum numeric character
  • Minimum punctuation character
  • Forbid user to use username within password
  • Forbid user to use password that listed in weak password list.

Continue reading “Enhance ClearOS 6 Password Policy”

Using HTTPS on CherryPY

Here’s CherryPY app configuration for using HTTPS:


cherrypy.config.update({
  'server.ssl_module': 'builtin',
  'server.ssl_certificate': '/opt/myapp/conf/cert/cert.crt',
  'server.ssl_private_key': '/opt/myapp/conf/cert/cert.key',
})

for ssl module module you can use builtin or pyopensll (by installing pyOpenSSL module). Use this command if you want create self sign certificate.

openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout cert.key -out cert.crt

Dump & Restore MongoDB With Specified Collection and DB

For example i have collection with name logs and db postfix, the output for dumped DB will be located to /tmp/backupmong


mongodump --out /tmp/backupmong/ --collection logs --db postfix

The command above will generating 2 files .bson and .metadata.json

Here’s the command for restoring the database (collection) by using .bson file.


mongorestore /tmp/backupmong/postfix/logs.bson -d anotherdb -c anotercol