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Firefox v30 does not handle NTLM v2 properly

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  • 5 have this problem
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  • Last reply by tomb-11

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Following upgrade to Firefox v30, with network.negotiate-auth.allow-insecure-ntlm-v1 defaulting to 'false', users are unable to authenticate, even though NTLM v2 is being used. NTLM v1 had to be re-enabled for backward compatibility and network.negotiate-auth.allow-insecure-ntlm-v1 had to be set to 'true' for Firefox to support authentication.

Following upgrade to Firefox v30, with network.negotiate-auth.allow-insecure-ntlm-v1 defaulting to 'false', users are unable to authenticate, even though NTLM v2 is being used. NTLM v1 had to be re-enabled for backward compatibility and network.negotiate-auth.allow-insecure-ntlm-v1 had to be set to 'true' for Firefox to support authentication.

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NTLMv2 won't work on Firefox on non-windows machines.

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That should be fixed.

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Release notes for v30 state: "network.negotiate-auth.allow-insecure-ntlm-v1

   Introduced in Forefox 30 on April 25th, 2014, disables use of our own internal implementation of NTLM module that talks only NTLMv1."

For Firefox to be a viable browser in corporate networks, the NTLM module needs to be updated to talk NTMLv2.