My IP address appears to have been blocked - What to do?

I have had the same IP address via Zen for over 10 years now which is very useful to me as I am required to have a static IP address for access to my secure network at the University I work at and various research databases and projects that I am working on.

This morning I have noticed that I can no longer access various websites (examples - tesco.com, sky.com, ebay.co.uk, cbc.ca) as I get an Access Denied 'You don't have permission to access "http://groceries.tesco.com/groceries/" on this server. Reference #18.d5d2dead.1620387505.2ffd2a0" - the reference number at the end isn't static and changes with a refresh.

If I attempt to connect to any of these sites via 4g on my phone they work fine, switch wifi on my phone (i.e. direct the traffic via Zen) and it is back to access denied. Connecting via the University secure VPN (traffic via JANET) and the sites work fine again.

I've spoken to Zen and done all the usual things, flushing DNS cache, changing DNS, rebooting hardware and nothing worked.

Then Zen gave me access to a test username and password which took me away from my static IP address and on to another IP addresses and everything started working again.

Zen's tech support and my line of reasoning suggests that it looks like my IP address has been blocked somehow and all they can suggest is getting a new static IP. Before I do this, however, is there anything else I could try or even find out how my IP address has come to be blocked and by whom? I'd rather not change IP address as I would need to contact a few different people to set things up again, so any suggestions would be gratefully received

How do you know whether your internet connection is working at all? Can you get a ping response from the sites that you mention?

Thank you for replying.

I know my connection is working as I'm using the connection right now to read your response and to write this reply

Not every single site is blocking me.

I can ping tesco.com absolutely fine,

Pinging tesco.com [156.154.240.85] with 32 bytes of data:
Reply from 156.154.240.85: bytes=32 time=14ms TTL=246
Reply from 156.154.240.85: bytes=32 time=14ms TTL=246
Reply from 156.154.240.85: bytes=32 time=14ms TTL=246
Reply from 156.154.240.85: bytes=32 time=14ms TTL=246

But I get the access denied message when I try to visit it.

So far, I've found that the following sites are blocking me

Tesco.com
Sky.com
Ebay.co.uk
cbc.ca

But there are bound to be more

In reply to a post by Michael_Chare:

How do you know whether your internet connection is working at all? Can you get a ping response from the sites that you mention?

If it was giving a blocked response to websites, but connecting to work then using work as a vpn to connect its clearly the IP that is blocked

Without googling its probably a content delivery network (cloudfare) that has had an issue with your IP, or more likely a very close one and blocked a range.

In reply to a post by Hewitt_Himself:

Without googling its probably a content delivery network (cloudfare) that has had an issue with your IP, or more likely a very close one and blocked a range.

Thank you for flagging that, is there anything I can do from my end to research this any further?

Check your IP reputation at one of the free online sites such as
https://mxtoolbox.com/blacklists.aspx
https://talosintelligence.com/reputation_center/lookup

This may shed some light.

NB if you have IPv6 be sure to check both your v4 and v6 addresses

Thank you for those links they were really helpful.

I've checked my IP address on both of them (v4 only as i don't have v6) and it comes up clean on both, so I don't seem to be on any blacklists.

Unless, that is, they aren't updated regularly, as I placed by grocery order on Tesco.com last night just after 10pm, so it was certainly working then and I didn't notice it wasn't working today and I was blocked until about 9.30am

In reply to a post by Spudgun:

I can no longer access various websites (examples - tesco.com, sky.com, ebay.co.uk, cbc.ca) as I get an Access Denied 'You don't have permission to access "http://groceries.tesco.com/groceries/" on this server. Reference #18.d5d2dead.1620387505.2ffd2a0" - the reference number at the end isn't static and changes with a refresh.

Hi, the websites you've mentioned all use Akamai. Have a look at Akamai's reputation checker.

https://www.akamai.com/us/en/clientrep-lookup/

https://community.akamai.com/customers/s/article/Why...

> dig +short www.cbc.ca
san.cbc.ca.edgekey.net.
e5220.e12.akamaiedge.net.
2.16.57.134
> dig +short www.tesco.com
www.tesco.com.edgekey.net.
e2008.x.akamaiedge.net.
23.195.134.84
> dig +short www.sky.com
www.sky.com.edgekey.net.
e1264.g.akamaiedge.net.
92.122.18.173
> dig +short www.ebay.co.uk
slot11847.ebay.com.edgekey.net.
e11847.g.akamaiedge.net.
88.221.42.201

Thank you - that has identified the problem exactly

Your IPv4 Address *redacted* received a bad risk score.

The IPv4 Address was associated with the following malicious activity:

Web Attacker

I've completed the form on their website to enable an investigation into this and hopefully they will be able to see that I've done nothing wrong.