O2-owned ISP Be is fighting a constant battle to stay one step ahead of hackers because of a router vulnerability exposed back in February.
Be subscribers were exposed when London student Sid Karunaratne demonstrated it was possible to gain remote root access using poorly concealed telnet backdoors. Admin usernames and passwords had been left accessible by Be.
Details of the original exploit are here.
Be responded by first accusing Karunaratne of hacking its internal network, and then booting him off the service. It released a firmware update in March which tightened up the access control list for the telnet service ports.
However, it's emerged that whenever the router is reset to factory settings - which Be recommends as part of the procedure for switching from a dynamic to a static IP, for example - the configuration is refreshed with the original access control list, leaving it wide open once again. Customers sometimes restore factory settings when the router crashes too.
Routers sent out since the update don't have the vulnerability. Be says it addresses it in older models by flashing the firmware repeatedly everyday. It sent us this statement:
Access is restricted to specific IP addresses. This is managed through new firmware we released in March 2007. All new members that have joined since then have received Be Boxes with the updated firmware on. For all members that joined prior to that Be runs a script multiple times a day to update members firmware with the relevant patch.
It asked users to get in touch if they're having problems.
New O2 broadband customers, who will be using the Be ADSL2+ network, won't be affected by the constant need to flash the firmware*. ®
*Correction: Several readers wrote to point out our error that they are updating the ACL templates, not flashing the firmware. Apologies for the mistake.
Thanks to Finlay for the heads up.