It looks like if you want to save your privacy, you will need to invest in official accessories for your smartphone. There has been reports of the Galaxy S10 and Note 10 devices giving access to anyone with a finger to unlock it.
News UK company The Sun reported one woman who discovered this issue after fitting a £2.70 screen protector from eBay. Another S10 user has shared on Twitter of a similar issue as well, with a video to where she placed a transparent phone cover on the screen to easily unlock a phone that was not hers. It's important to note that this won't just affect unlocking the smartphone, but people will also be able to access important information like your bank or payments which uses fingerprint scanning to access.
Samsung had already warned users about using unofficial accessories, especially scratched or even dirty screen protectors as it may lead to the fingerprint sensor to not function properly. After all this has been revealed though, Samsung has released a statement that they are currently investigating the issue and will be releasing a software patch soon to fix the matter.
But even then, it's highly recommended that you get an official screen protector from Samsung before then. The S10 already comes with a default screen protector that doesn't appear to have the same vulnerability as when using unofficial ones.