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Why does Firefox (v39) not allow me to access my router (Cisco RV042G) but Internet Explorer will? How can this be fixed?

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Firefox will not allow me to access my Cisco RV042G router (192.168.1.1). However IE will allow me to access it. How can this be fixed?

Firefox will not allow me to access my Cisco RV042G router (192.168.1.1). However IE will allow me to access it. How can this be fixed?

All Replies (8)

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Do you get an error message when you try to access your router? What is that message?

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Error that I receive:

Secure Connection Failed

An error occurred during a connection to 192.168.1.1. SSL received a weak ephemeral Diffie-Hellman key in Server Key Exchange handshake message. (Error code: ssl_error_weak_server_ephemeral_dh_key)

   The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
   Please contact the website owners to inform them of this problem.

_________________ Does not matter if I try secure or not... I've even tried Safe Mode....

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Can you update your router's firmware? This is happening because it has and out of date security protocol. If this is a problem there are likely other security issues, but there may be an update to fix it.

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Hi Grandpappy, this error message indicates that the router is trying to use an obsolete encryption cipher which is vulnerable to the "Logjam" attack that was in the news earlier this year.

What does that mean?

Even though you trust the router, a "Logjam" attack compromises the security of your individual connection to the server, lowering the protection normally provided by SSL to a level that is easily cracked and read by others on the network. That is why Firefox protects you from making this connection.

Now... with an internal device, this may not seem like much of a concern but if your network does have an intruder, this attack would allow them to read your login for the router, which could lead to other problems.

What can you do now?

The very best solution is to update the device. However, if that is too complicated, you can try disabling these old ciphers in your Firefox, which hopefully will force the router to try some more secure ciphers when connecting with you. Here's how:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the search box above the list, type or paste dhe and pause while the list is filtered

(3) Double-click the security.ssl3.dhe_rsa_aes_128_sha preference to switch it from true to false (disable Firefox from using this cipher)

(4) Double-click the security.ssl3.dhe_rsa_aes_256_sha preference to switch it from true to false (disable Firefox from using this cipher)

Then try the device again; you might have to reload the page using Ctrl+Shift+r to bypass cached information.

Success?

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I already used IE to access the router and update the firmware. And yes I saw the "Logjam" solution and tried that to no avail. I guess I'll be stuck using IE to access my router.

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Can you not update your router?

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For what it's worth, there appears to be a firmware release dated June 2, 2015.

http://www.cisco.com/c/en/us/support/routers/rv042g-dual-gigabit-wan-vpn-router/model.html#~tab-downloads