Iran blocking SSL connections

By | February 9, 2012
The latest in censorship news: Iran is blocking SSL connections. It seems to be pretty basic and targeted filtering so far, so nothing that can't be worked around with some help from non-iranian groups interested in protecting the ability to communicate and organize civilian efforts, but it is a worrying sign that internet monitoring and resulting potential implications for supressing unwanted opinions is again on the rise.

Reshared post from +Sai

I have pretty definitive proof that Iran is doing ip-and-port based filtering of SSL.

Filtering is being done by after a hop through / This hop is after my source's ISP, and all three IPs are owned by ITC, Iran's central telco.

Filtering targets all IPs, some but not all IPs, probably more. Haven't attempted a broad scan. It's a simple connection drop; filtered connections just time out.

It is not based on SSL handshake signature; testing SSL on nonstandard ports worked successfully, and testing non-SSL on :443 of target IPs was blocked.

I'm not sharing screencaps in order to protect my source, but tests included TCP traceroutes on different IP/port combinations and some simple use of curl.

One thought on “Iran blocking SSL connections

  1. Sophie Wrobel

    +Sai Iranians have a certain resiliency to cyber restrictions, often finding alternate solutions. Google services in general is a problem over there, as with many other US-based services – at least from what I hear, not only in terms of access and filtering but also worries about eavesdroppers. While I am also aware of additional filtering taking place, I'm not so sure that Google result tampering has as much of an effect as you may think.


Leave a Reply

Your email address will not be published.