The polyfill.js is a popular open source library to support older browsers. 100K+ sites embed it using the cdn.polyfill.io domain. Notable users are JSTOR, Intuit and World Economic Forum. However, in February this year, a Chinese company bought the domain and the Github account. Since then, this domain was caught injecting malware on mobile devices via any site that embeds cdn.polyfill.io. Any complaints were quickly removed (archive here) from the Github repository.
nah. over 100k sites ignored dependency risks, even after the original owners warned them this exact thing would happen.
the real story is 100k sites not being run appropriately.
This is why ublock origin is an essential security tool.
What rules can we add that solve this problem? (I’ve tried DDG but didn’t find any results)
This one is already in the default
uBlock filters - Badware risksI also strongly suggest adding https://big.oisd.nl/ as a filter list. It’s a large and well maintained domain blocklist (sourced from combining lots of other blocklists) that usually adds lots of these sorts of domains quickly and has very few false positives.
If you want to take it even further, check out the Pro list and Thread Intelligence Feeds list here https://github.com/hagezi/dns-blocklists
These can all be added to a pihole too if you use one.
What’s the malware do?
Frustrating that the article doesn’t specify and simply links to a different Github page which doesn’t clearly specify the problem either.
I have to assume the site’s article was dynamically generated, without any actual tech journalist doing the reporting. The byline is “Sansec Forensics Team” which doesn’t even link out to the group. Also, the “Chinese Company” isn’t named either it the article or the references, which is incredibly shoddy reporting. The archive link is dead.
This whole page is indicative of the failed state of tech journalism. A genuinely explosive story but its so threadbare and vague that it becomes meaningless.
