Security Certificate issue accessing Github

[phvm]

I am currently unable to access github.com, due to a claimed security certificate issue, however if I jump on a VPN or if I use mobile data I am able to access Github perfectly fine. This has happened with other sites in the last couple months, for example mega.nz. I was unable to access mega.nz for about a month, but then it just started working again. Same as now, if I jumped on a VPN I could access Mega perfectly fine. I asked friends of mine who also use Virgin Media broadband if they could access it, and they could, so the issue was between my area and destination.

• Using incognito doesn't help
• I've reset my router
• Confirmed I can access the site via other providers (o2 mobile network, Nord VPN)
• Confirmed other Virgin Media Broadband users can access the site

[Client62]

Check an nslookup of the site with the VM DNS returns the correct IP.

[phvm]

Here is the result of the nslookup

[Client62]

Any chance you have a VM Hub 5 in Router mode and in the VM Connect app
you have a function named Smart Security or a similar title that is Enabled ?

What we can see is the VM DNS lookup has been intercepted and your lookup redirected to a DNS named
uk-blockpage.prod.lg.securingsam.com

Here is my nslookup via a Hub 3 in Router mode...

C:\Users\Philip>nslookup github.com
Server: cache1.service.virginmedia.net
Address: 194.168.4.100

Non-authoritative answer:
Name: github.com
Address: 20.26.156.215

[phvm]

Yes I have VM Hub 5 and it has Smart Security enabled (both Safe browsing and Network protection).
Should I test it by turning it off?

[用心棒]

Virgin Media's Smart Security service is blocking site; read more here, Virgin Media O2 adds another layer of smart security for thousands of customers at no extra cost - V.... Look into configuring Smart Security to allow site.

FWIW: when access to a site is blocked the following page cannot be shown over an authenticated / secure connection (i.e. HTTPS) due to inbuilt browser protections.

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[phvm]

How do I configure it to allow the site though? In the connect app there only looks to be the option to turn off smart security.

[Client62 · Accepted solution]

I have Child Safe disabled & Virus Safe disabled in the VM online account.

I would turn off Smart Security in a heart beat.

My choice is no ISP filtering, the problem is exactly what we see today, it does go wrong and stop the job in a totally obscure manner.

We do not use the VM Connect app, i.e. we do not have it installed on our mobiles as it is a well known to tinker with the Hub Wi-Fi settings and now we also see it enables Smart Security which has proved to be yet another point of failure.

[phvm]

Okie doke, I will probably just turn it off, I have Unifi acting as a firewall for me, so no need to have ISP filtering also. Didn't even realise it was enabled until you pointed me to it to be honest. Thank you for your help.

[phvm]

Yup.. turned it off, can now access Github!