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not the slam dunk I had hoped for but useful none the less thanks
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not the slam dunk I had hoped for but useful none the less thanks

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Hello I noticed I have a security flaw in my system whereby if I am located internally of the network and telnet to my mail server I can create an email message and send it without authenticating, thereby allowing users to create a bogus senders address and spam valid senders within our environment. I was looking at potential ways of preventing this from happening. One thought was to to create a lan to lan firewall rule allowing access on port 25 only on the email server, so deny all others lan to lan traffic on port 25 just wasn't sure if I would be impacting on other areas working effectively. for example my proxy server emails out when it has an issue etc. so might need to restrict it to all servers, unless someone else can offer some alternative suggestions to prevent this behaviour. My email system is groupwise 8 and I have a cyberoam firewall.
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Hello I noticed I have a security flaw in my system whereby if I am located internally of the network and telnet to my mail server I can create an email message and send it without authenticating, thereby allowing users to create a bogus senders address and spam valid senders within our environment. I was looking at potential ways of preventing this from happening. One thought was to to create a lan to lan firewall rule allowing access on port 25 only on the email server, so deny all others lan to lan traffic on port 25 just wasn't sure if I would be impacting on other areas working effectively. for example my proxy server emails out when it has an issue etc. so might need to restrict it to all servers, unless someone else can offer some alternative suggestions to prevent this behaviour. My email system is groupwise 8 and I have a cyberoam firewall.

Configure Firewall to block smtp access to server on internal network

An email client, email reader or more formally mail user agent (MUA) is a computer program in the category of groupware environments used to access and manage a user's email. A web application that provides message management, composition, and reception functions may internally act as an email client; as a whole, it is commonly referred to as webmail. Likewise, email client may be referred to a piece of computer hardware or software whose primary or most visible role is to work as an email client. Email clients can also have other systems, like calendars, notes and contact managers.

Email Clients

Hardware-based firewalls provide more sophisticated protection for inbound and outbound traffic than the simple Windows software firewall or the basic NAT firewalls found in routers. These devices implement techniques such as stateful packet inspection, deep packet inspection, and content filtering; and may include built-in antivirus and anti-malware protection.