The problem is due to the incorrect configuration of at least one Telstra email server, according to an announcement on www.whirlpool.net.au This server is categorised as an "open relay" because it allows anybody to relay outgoing emails through the server without being a BigPond user - an open invitation to spammers who send thousands of unsolicited emails, leaving Telstra (and its end users) to cop the cost.
Online organisations, such as Relay Spam Stopper (RSS), test servers and publish information of those that are insecure - providing administrators with the means to block their servers to incoming emails from open relay servers. These emails bounce back to the sender.
-We've started noticing a large number of our emails bouncing back," Whirlpool's Dan Warne told ZDNet Australia. "Telstra really should have this basic security issue sorted out by now."
Warne claims that protecting a mail server form relay access is "extremely simple" to do and that BigPond users will have -ongoing issues" until the telco heavyweight patches the hole.
"It points to a business problem at their [Telstra's] end - they haven't audited the security of servers adequately," Warne said.
Telstra said it was aware of the problem and was investigating whether it was one of its own servers or that of a customer that was wrongly configured.
The RSS Web site has a database of -spam on file" which is purportedly sent from BigPond servers.
-A well-configured mail server should not relay third-party email, otherwise the server is subject to attack and hijack by Internet vandals and spammers," an RSS message says.
Telstra's ADSL email servers are open spammers. I have had numerous emails bounced trying to communicate with my friends whose ISP's actively check for this type of behavour. When I wish to email my friends, I have to use another email provider. ie;webmail such as yahoo.
Telstra have ignored my complaints totally. Why should I be surprised. Their ABUSE section is just as bad.