Let’s say, I create a bank with the caveat that all of my banking phone apps and webapps are FOSS (or if they depend on non-free components — banks probably do to communicate with each other —, then just OSS). Am I going to be behind the competition by doing this?
If the most secure crypto algorithms are the ones that are public, can we ensure the security of a bank’s apps by publicizing it?
Are they not doing this because they secretly collect a lot of data (on top of your payment history because of the centralized nature of card payments) through these apps?
EDIT: Clarifying question: Is there a technical reason they don’t publicize their code or is it just purely corporate greed and nothing else?
What incentive would a bank have to release their apps as FOSS?
You probably could create an open source banking app and use it to run a bank on a primarily open source software stack. But banks are not software companies, and they have no reason to engage with the FOSS world. We could think up lots of potential reasons for why a bank might not want to release their apps as FOSS, but the simplest answer is “why would they?”
I’d love to live in a world where free software is the norm, but we’re not in that world. So if the bank has no incentive to do it other than the comparatively niche interests of the FOSS community, they just won’t do it.
There is also a lot of “security by obscurity” in the corporate/fintech world - “it’s open source so everyone can see the code which makes it less secure”. The inverse is often true thanks to Linus’s Law.
The article you linked seems to suggest that Linus’s Law is a mere suggestion, at best.
No one is suggesting that open source is inherently less secure, just that the vulnerabilities are easier to find, and thus easier to get exploited. For a third party reviewer there’s a lot of incentive not to report bugs they would find in banking software.
Unfortunately, I’ve met a number of people who genuinely do believe this! The same demographic who don’t know how copy and paste works or take photos of stuff on their monitor instead of print-screening and tend to end up running large corporations even though they’re completely out of touch.
Indeed they wouldn’t because most consumers are pushovers, willing to fetch and run any garbage non-free software and willing to share sensitive data with Google in the process. So there’s no reason to offer a FOSS option – as people are not demanding it.
I am one of the very few who demand FOSS. I will not run a non-free app (esp. banking) and I will not create a Google account to reach their exclusive playstore. And now that bank’s web services have started going to shit (blocking tor, reducing web features or simply being shut down to force people to use the phone apps), I’ve gone analog. If a critical mass of consumers were to do the same and stand up for themselves, banks would be forced to do the right thing. But they are not. Ethical consumers are too small of a group to be worth getting business from.