Santander customers are continuing to complain about receiving trojans and other junk to email addresses exclusively used with the bank. The reports began last month, prompting promises of an investigation by Santander. It's still unclear whether email addresses leaked from the bank or one of its affiliates.
Independent experts said that fingering the source of this type of leak can be hard to determine.
We first heard of problems from Reg reader “Paul” in mid November. "In the last few days, I've started to receive a number of spam/virus emails sent to a unique email address only given to and used by the Santander bank to contact me," he told us.
Checks at the time revealed that Santander had already launched an investigation in response to similar reports, as SC Magazine reported in early November.
A trojan was being sent to private email addresses that, according to complaints and reports, should only have been known by institutions including Santander Bank, the UK Government Gateway and NatWest's FastPay service. The attacks were first detected by Belgian security firm MX Lab.
A substantial sample of the offending emails contain reference to a supposed "Direct Debiting Seminar Invite" and a trojan in an attached ZIP file, as explained in a blog post by MX Labs here.
Attacks against unique email addresses registered with Santander have continued into December, with another Reg reader reporting the problem a few days ago. It's unclear whether or not this is the second wave of the same attack.
Reg reader “Andrew” told us: "It appears that Santander may have had a data-breach: the customised unique email address I gave exclusively to them is now being used to send me junk email, trojans."
According to a thread on UK financial advice website Money Saving Expert, Andrew and Paul are far from the only one to run against this problem. There's been a steady stream of reports on the issue since mid-November.
There's no suggestion that any of the bank's more sensitive systems are leaking, but those who submitted posts to the MSE thread are worried about the junk mail they're receiving after email addresses supplied to the bank somehow leaked out.
In a statement, Santander told El Reg that it's continuing to investigate a possible data breach involving email addresses supplied to them:
Our investigation is ongoing. If, when it is completed, a breech [sic] has occurred we will follow the correct procedure in reporting this to the relevant authorities.
These kind of problems crop up regularly and are far from limited to Santander. It's a familiar story: someone receives a malicious email address in a unique email address box only used to register an account with one entity (typically a bank). They cry foul and tell us the bank must have had its email database breached. This is a regular theme of items in Vulture Central's mailbag.