Internal data breaches might keep CSOs awake at night, but they appear to be a rare event, a university analysis of reported UK compromises has found.

In the UK Security Breach Investigations Report the University of Bedfordshire crunched data on incidents reported to forensics firm 7Safe, finding that the overwhelming majority came from external sources.

Of the 62 breaches 7Safe was called in to investigate across a range of sectors, 80 percent were found to be external in origin, 18 percent came from business partners, leaving only 2 percent to be blamed on insiders.

Sixty-nine percent of these happened in the retail sector, mainly in online commerce, leaving finance in its wake with 7 percent, IT and services with 4 percent, and councils with 2 percent.

In 85 percent of the cases, 7Safe found that the compromised information was payment and card data, and the main attack route was through the sort of unsophisticated SQL injection attacks databases are supposed to be able to resist. Shared hosting was a common theme, whereby an attacker undermines one website and uses the same vulnerability to attack others on the same host.

"A lot of them are not particularly sophisticated attacks," reinforces 7Safe co-founder and CEO, Alan Phillips. "It is just poor coding of these websites."

According to Phillips, this raised a question mark over the effectiveness of mandatory regimes such as the industry Payment Card Industry Data Security Standards (PCI DSS). Problems included flawed self assessment and the over-use of automated compliance tools.

"Automated scans don't pick everything up as would a person," says Phillips. Scanners would only test accessible pages, for instance, whereas a human would look for further login pages not so easily reached. Vulnerabilities might lie on these unnoticed by bots.

Standing back from the figures it is hard to know how accurately the breach proportions in this report reflect wider business experience. As Phillips himself acknowledges, internal hacks are almost certainly under-reported for a variety of reasons and the UK lacks any legal requirement to report breaches of any sort. It also doesn't give many clues as to the seriousness of a breach as opposed to its frequency.

Online data is clearly, however, a soft underbelly for criminals. "The analysis proves that many organisations who declare themselves compliant with the PCI Data Security Standards are not even close," the report concludes.