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Cisco Umbrella blocking several sites

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I try to access several of my bookmarked sites only to have Cisco Umbrella block them. I unchecked the block sites" in the security settings to no avail. I have a right to access any site I wish. Also, Firefox is the only browser that does this to me. Please help.

I try to access several of my bookmarked sites only to have Cisco Umbrella block them. I unchecked the block sites" in the security settings to no avail. I have a right to access any site I wish. Also, Firefox is the only browser that does this to me. Please help.

All Replies (5)

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Hi

That sounds like a corporate or organisation tool used by the network administrator. I recommend that you contact your IT suppor team as this does not sound like an issue with Firefox.

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I don't have any it administrator. I'm just an individual person with a MacBook Air

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Yes, I've had to deal with this issue. Umbrella intercepts various requests to either check them or block them. In order to insert itself, it needs to present a fake site certificate, which Firefox naturally does not trust. So why does it work in other browsers? Umbrella installs the master certificate it uses to sign its fake site certificates in the system certificate store, but not into Firefox's. To deal with that, you have two choices:

(1) Set Firefox to use the system certificate store, or (2) Set up Firefox to trust the Umbrella certificate

For #1:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.

(2) In the search box in the page, type or paste security.enterprise_roots.enabled and pause while the list is filtered

(3) Double-click the preference to switch the value from false (use Firefox's own certificate store) to true (accept certs from the system certificate store)

You might have to Quit and restart Firefox before that change takes effect.

For #2:

Cisco published the steps, but only your account administrator has access to download the certificate: https://docs.umbrella.com/deployment-umbrella/docs/install-cisco-umbrella-root-certificate#firefox

On Windows, it's possible to export the certificate from another browser as a workaround, but I don't know whether that is an option on Mac OS.

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rblumpr55 said

I don't have any it administrator. I'm just an individual person with a MacBook Air

Do you have an OpenDNS subscription? Otherwise, why would Umbrella be involved in your Mac security. Strange.

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In the past, some malware hijacked a third party certificate to look less suspicious, so if you aren't actually runnning Umbrella, it would be a good idea to scan:

https://www.malwarebytes.com/mac