How do we know if there aren't a bunch of more undetected backdoors?
I have been thinking about self-hosting my personal photos on my linux server. After the recent backdoor was detected I'm more hesitant to do so especially because i'm no security expert and don't have the time and knowledge to audit my server.
All I've done so far is disabling password logins and changing the ssh port.
I'm wondering if there are more backdoors and if new ones are made I can't respond in time.
Appreciate your thoughts on this for an ordinary user.
We don't know. But if there were well known backdoors to mainstream security practices we might see more companies that depend on security shutting down, or at least shutting down their online activities. Banks, stock trading, crypto exchanges, other enterprises that handle money, where hacking would be lucrative.
I don't think you need to worry about backdoors with most of those. Worry more about unfixed security holes due to an extreme emphasis on "stability" as in using old versions when fixes have already been released when it comes to anything hosted by large companies.
There's a concept of acceptable levels of risk. Companies are not going to shut down out of fear, or miss out on the business opportunities of online presence. There's money to be made.
Even with things as serious as spectre allowing full dumping of CPU and RAM contents simply by loading a website, I can't think of a single company that just said "well shit, better just die".
Serious, potentially business ending, security issues usually have a huge amount of effort when discovered put into mitigations and fixes. Mitigations are usually enough in the immediate "oh shit" phase. Defense in depth is standard practice.