Users worldwide are not able to access Facebook, Instagram, and WhatsApp services due to a BGP problems. Users attempting to visit the above services are displaying “DNS_PROBE_FINISHED_NXDOMAIN.”
The mobile applications of the social network giant and its Tor hidden services are also not working.
At the time of this writing, it is unclear if the outage is the result of a technical issue or it is the result of a cyber attack against the infrastructure of the social network giant.
John Graham-Cumming, CTO at Cloudflare, reported that some minutes before Facebook’s DNS outage began they observed a large number of BGP changes for Facebook’s ASN a circumstance that suggests BGP routing problems. The expert also warned of a massive flood of DNS traffic asking for http://facebook.com.”
“Now, here’s the fun part. @Cloudflare runs a free DNS resolver, 220.127.116.11, and lots of people use it. So Facebook etc. are down… guess what happens? People keep retrying. Software keeps retrying. We get hit by a massive flood of DNS traffic asking for http://facebook.com” states the Graham Cumming.
“But that’s not all. Now human behavior and application logic kicks in and causes another exponential effect. A tsunami of additional DNS traffic follows.” reads a post published by Cloudflare. “This happened in part because apps won’t accept an error for an answer and start retrying, sometimes aggressively, and in part because end-users also won’t take an error for an answer and start reloading the pages, or killing and relaunching their apps, sometimes also aggressively. This is the traffic increase (in number of requests) that what we saw on 18.104.22.168”
“We’re aware that some people are having trouble accessing our apps and products. We’re working to get things back to normal as quickly as possible, and we apologize for any inconvenience.” Facebook communications executive Andy Stone wrote on Twitter.
To better understand why Facebook disappeared from the Internet give a look at this excellent post from Cloudflare:
Immediately after the service were sliding going up again the popular investigator Brian Krebs posted:
Update: 11:00 PM GMT, October 4, 2021:
After more than six hours of outage, Facebook, Instagram, and WhatsApp are slowly coming back online:
Below is my interview at TRT: What does the outage say about Facebook’s own security and infrastructure?
(SecurityAffairs – hacking, social network)