FFOX-00-000027 - Firefox deprecated ciphers must be disabled.

Information

A weak cipher is defined as an encryption/decryption algorithm that uses a key of insufficient length. Using an insufficient length for a key in an encryption/decryption algorithm opens up the possibility (or probability) that the encryption scheme could be broken.

Solution

Windows group policy:
1. Open the group policy editor tool with 'gpedit.msc'.
2. Navigate to Policy Path: Computer Configuration\Administrative Templates\Mozilla\Firefox\Disabled Ciphers
Policy Name: TLS_RSA_WITH_3DES_EDE_CBC_SHA
Policy State: Enabled

macOS 'plist' file:
Add the following:
<key>DisabledCiphers</key>
<dict>
<key>TLS_RSA_WITH_3DES_EDE_CBC_SHA</key>
<true/>
</dict>

Linux 'policies.json' file:
Add the following in the policies section:
'DisabledCiphers': {
'TLS_RSA_WITH_3DES_EDE_CBC_SHA': true
}

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_MOZ_Firefox_V6R5_STIG.zip

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-7a., CAT|II, CCI|CCI-000381, Rule-ID|SV-251571r879587_rule, STIG-ID|FFOX-00-000027, Vuln-ID|V-251571

Plugin: Windows

Control ID: c4b63c89bf119e308a89d1c547fe6f08797337f4a78694d98fab8f03bd42c547