Top all-time · #19008
The Twenty Percent
Personal blog · kuenzi.devhardwareprogramming
The Twenty Percent is a personal blog at kuenzi.dev about hardware and programming. Since 2023, 4 different Hacker News readers have linked it 4 times, most often “Hacking My "Smart" Toothbrush”. The last post was in 2024, but the archive is still widely read.
Too few sampled comments (2) to say how often HN recommends it.?
Why HN links it
HN readers link kuenzi.dev for its reverse engineering of a Philips Sonicare toothbrush's NFC password and timer, a follow-up to an earlier post about investigating the same toothbrush.
Summarised by Claude from a sample of 2 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
Personal Blog about electrical engineering, IT and finishing projects.
Most-linked posts?
- Hacking My "Smart" Toothbrush3 people · 3 mentions · first linked 2023-05-30
What Hacker News says?
Apparently someone reverse engineered the firmware[0] to find it. I don't see how they could easily change the password, except for perhaps using a custom tag that would only allow incrementing the values with the existing password (which would negate the point of changing the password). Otherwise it would lock existing brushes out of saving the time too. This, combined with how 99% of the users won't be tevh-savvy…
Comment linking /toothbrush/
on “Resetting the timer in my toothbrush”Submitted Hacking My "Smart" Toothbrush as a story · 3 points
HN discussionThis is my favorite kind of HN content, people following their curiosity. This a double-deal since the original story ( https://kuenzi.dev/toothbrush/ ) had someone trying to investigate their toothbrush, someone else couldn't stop thinking about the story, and decided to take it further. Thanks for posting this!
Comment linking /toothbrush/
on “Hacking the Philips Sonicare NFC Password”Submitted Hacking a Philips Sonicare Toothbrush as a story · 2 points
HN discussion