Turkey blocked Twitter following deadly earthquake

On 8th February 2023, following a devastating 7.8-magnitude earthquake that resulted in more than 36,000 deaths, access to Twitter was restricted in Turkey.

OONI data collected from Turkey provides evidence that the block was implemented through targeted throttling and DNS interference.

The above chart aggregates OONI measurement coverage from the testing of Twitter (twitter.com) on multiple networks in Turkey between 9th January 2023 to 9th February 2023. As is evident, the testing of Twitter was mostly successful throughout this period, only presenting noticeable anomalies on 8th February 2023, which correlates with the date of the reported block. Across networks, we observe anomalies between 13:21 UTC to 21:33 UTC on 8th February 2023 (though the first anomaly is observed as early as 08:31 UTC on AS202561), suggesting that access to Twitter was restricted in Turkey on that day.

An analysis of OONI data shows signs of Twitter throttling on at least 4 ASNs in Turkey. Starting from ~ 13:30 UTC on 8th February 2023, the TLS handshake time for IPs associated with twitter.com grows substantially. Specifically, successful TLS handshakes took more than 3 seconds to complete, whereas they previously took ~ 70ms. We did not find the same pattern for other tested endpoints on the same networks during the same time period, suggesting that access to Twitter was throttled. On other networks, such as Vodafone (AS15897), OONI data shows that access to Twitter was blocked by means of DNS tampering (as the localhost IP 127.0.0.1 was returned as part of DNS resolution).

Learn more through our research report.