The largest data breach disclosed this month was by T-Mobile , the telecoms giant said there had been "unauthorised access" to potentially 2 million of their 77 million customer accounts. According to the media, a hacker took advantage of a vulnerability in a T-Mobile API (application programming interface). It was a vulnerable API used by Air Canada mobile App which was also exploited, resulting in the compromise of 20,000 Air Canada customer accounts . Air Canada promptly forced a password change to all of its 77 million customer accounts as a result, however, the airline faced criticism from security experts for advising a weak password strength. Namely, a password length of 8, made up of just characters and digits. Both of these hacks underline the importance of regularly penetration testing Apps and their supporting infrastructure, including their APIs. Hackers stole up to 34,000 Butlin guest records, reportedly breaching the UK holiday camp firm through a p...