Turkey has blocked Twitter and YouTube, along with hundreds of other sites, following a court order. Graffiti is fighting the block by giving instructions on how people can update their DNS to use Google’s DNS at 18.104.22.168 and 22.214.171.124. The block was ordered because pictures of terrorists and their hostage were being shared on social media. Tor and VPNs should not be affected.
The telecoms are using a DNS cache poisoning attack to perform the block. DNS or Domain Name Service is a protocol that provides a way to turn human-friendly URLs such as www.example.eq to IP addresses like 126.96.36.1999. How the attack works is that a malicious DNS server will intentionally mistranslate the human-friendly address to an IP address owned by the attacker, who in this case is TurkTelecom. DNS poisoning is also used by malware to redirect you from, say, www.mybank.eq to an identical-looking site to steal your password.
This is not the first time Turkey has blocked websites. In 2014, just before local elections, Turkey’s President Erdogan vowed to “wipe out Twitter” following documents alleging corruption in his government appeared on Twitter.
You can ironically follow the block via Twitter hashtag #twitterisblockedinturkey.