Hello,
I have installed OpenWRT 18.06.1 on my Netgear 6220 router. I have configured HTTPS protocol (with my own self-signed certificate generated with openssl) and configured Luci to use it.
Until yesterday everything had worked flawlesly. Suddenly all browsers stopped connections to router using HTTPS protocol. Firefox displays error SSL_ERROR_NO_CYPHER_OVERLAP.
I cannot spot the reason for this error. I have upgraded packages in OpenWrt but this did not resolve problem. Nor did reinstalling libustream-mbedtls with dependencies.
I can connect with my router by HTTP and SSH without any problem, and besides HTTPS problem router seems to work fine.
Firefox 63.0.1 was released a few days ago, maybe it's related? I don't get this error, but I'm using libustream-openssl. It could also be caused by anti virus software intercepting the request.
Firefox 63.0.1 - error as in topic subject
Chrome 70.0.3588.77 - ERR_NETWORK_CHANGED
Edge 17.17134 - cannot securely connect with web site
Opera 56.0.3051.52 - same error as Chrome
I have removed self signed certificates. After reload uhttpd regenerated certificates, however it did not resolve my problem.
I suspected the ciphers to be a problem source however have no idea how to deal with it. Maybe replacing mbedtls with openssl libraries will be a solution?
I have installed libustream-openssl however problem is still not resolved.
Problem with Chrome comes probably from Bitdefender firewall - they do not like each other - a few months ago Chrome claimed that Bitdefender is dangerous and should be uninstalled.
It looks like Bitdefender is the root of the problem. I disabled SSL scanning and I was able to connect to my router with HTTPS. Then I installed certificate generated by router to Windows 10 CA Root store and then I was able to use HTTPS.
So it is most probably some problems with Bitdefender.