The latest Firefox STIG leaves out important details and lists settings that no longer exist. It took a few hours to get this config file to work with settings that are actually still available in 59.01. For reference, see: http://kb.mozillazine.org/About:config

Note that I use Notepad++ on Windows to avoid formatting issues with notepad.exe. Do yourself a favor and download the latest at https://notepad-plus-plus.org/

1) Create a file named local-settings.js and add one line. Using Notepad++, you can save it as a proper JavaScript file (.js):
pref(“general.config.filename”,”mozilla.cfg”);

2) Place local-settings.js file in the following locations depending on whether you have x32 or x64 bit Firefox:

For x64 bit:
C:\Program Files\Mozilla Firefox\defaults\pref

For x32 bit:
C:\Program Files (x86)\Mozilla Firefox\defaults\pref

3) Create a file called mozilla.txt. Add the text below (everything under contents of mozilla.txt staring with //Firefox). Launch a browser (Chrome, IE, Opera) and browse to:

http://www.alain.knaff.lu/howto/MozillaCustomization/cgi/byteshf.cgi

4) In the middle of the page, under Upload mozilla.txt to get mozilla.cfg (byteshift 13), click browse, and select your mozilla.txt file. Next, click Convert mozilla.txt to mozilla.cfg, and save the file when prompted.

5) Place the mozilla.cfg file into the root of the Firefox directory as show below.

For x64 bit:
C:\Program Files\Mozilla Firefox\

For x32 bit:
C:\Program Files (x86)\Mozilla Firefox\

6) Start Firefox. In the Location bar, enter about:config. Click I accept the risk. At the top of the page in the center, click Status to sort the status of the settings. All of the locked settings should be italicized with a status of locked.

Contents of mozilla.txt:

//Firefox settings that work from Mozilla_Firefox_V4R20 as of Firefox 59.01 March 2018
lockPref(“security.default_personal_cert”, “Ask Every Time”);
lockPref(“network.protocol-handler.external.shell”, false);
lockPref(“plugin.disable_full_page_plugin_for_types”, “application/pdf,application/doc,application/xls,application/bat,application/ppt,application/mdb,application/mde,application/fdf,application/xfdf,application/lsl,application/lso,application/lss,application/iqy,application/rqy,application/xlk,application/pot,application/pps,application/dot,application/wbk,application/ps,application/eps,application/wch,application/wcm,application/wbi,application/wb1,application/wb3,application/rtf,application/wch,application/wcm,application/ad,application/adp,application/xlt,application/dos,application/wks”);
lockPref(“browser.formfill.enable”, false);
lockPref(“signon.autofillForms”, false);
lockPref(“signon.autofillForms.http”, false);
lockPref(“signon.rememberSignons”, false);
lockPref(“dom.disable_window_open_feature.status”, true);
lockPref(“dom.disable_window_move_resize”, true);
lockPref(“security.tls.version.min”, 2);
lockPref(“security.tls.version.max”, 3);
lockPref(“dom.disable_window_flip”, true);
lockPref(“dom.event.contextmenu.enabled”, false);
lockPref(“dom.disable_window_open_feature.status”, true);
lockPref(“app.update.enabled”, false);
lockPref(“extensions.update.enabled”, false);
lockPref(“browser.search.update”, false);
lockPref(“datareporting.policy.dataSubmissionEnabled”, false);

7) Click the link below for a copy of the files. The zip has a converted mozilla.cfg, the source mozilla.txt, local-settings.js and a README file.

Firefox_STIGv4R20

This Firefox STIG leaves out important details. They could make it very simple to implement but they don’t.  For more, see: http://kb.mozillazine.org/About:config

1) Create a file called local-settings.js and add one line:
pref(“general.config.filename”,”mozilla.cfg”);

2) Place local-settings.js in:

c:\<firefox path>\defaults\pref folder.

3) Create a file called mozilla.txt. Add the text below (everything under contents of mozilla.txt).  Launch Firefox and browse to:
http://www.alain.knaff.lu/howto/MozillaCustomization/cgi/byteshf.cgi

4) View the middle of the page. Under Upload mozilla.txt to get mozilla.cfg (byteshift 13), click browse, select your mozilla.txt file. Next, click Convert mozilla.txt to mozilla.cfg, save the file when prompted and place it in c:\<firefox path>\Mozilla Firefox\.

Contents of mozilla.txt:

//Firefox Settings
lockPref(“security.tls.version.min”, 1);
lockPref(“security.default_personal_cert”, “Ask Every Time”);
lockPref(“network.protocol-handler.external.shell”, false);
lockPref(“plugin.disable_full_page_plugin_for_types”, “application/pdf,application/fdf,application/xfdf,application/lsl,application/lso,application/lss,application/iqy,application/rqy,application/xlk,application/xls,application/xlt,application/pot,application/pps,application/ppt,application/dos,application/dot,application/wks,application/bat,application/ps,application/eps,application/wch,application/wcm,application/wb1,application/wb3,application/rtf,application/doc,application/mdb,application/mde,application/ad,application/,application/adp”);
lockPref(“browser.formfill.enable”, false);
lockPref(“signon.autofillForms”, false);
lockPref(“signon.rememberSignons”, false);
lockPref(“privacy.sanitize.sanitizeOnShutdown”, true);
lockPref(“dom.disable_window_open_feature.status”, true);
lockPref(“dom.disable_window_move_resize”, true);
lockPref(“security.tls.version.max”, 3);
lockPref(“dom.disable_window_flip”, true);
lockPref(“dom.event.contextmenu.enabled”, false);
lockPref(“dom.disable_window_status_change”, true);
lockPref(“dom.disable_window_open_feature.status”, true);
lockPref(“browser.startup.homepage”, “about:home”);
lockPref(“app.update.enabled”, false);
lockPref(“extensions.update.enabled”, false);
lockPref(“browser.search.update”, false);
// The end

This is a quick post to show you how to enable legacy SSL and Java SSL support in your browser for those old, crusty websites and applications you have in your organization. Note that this should not be done on Internet facing systems. Only offline or systems that are not routed to the Internet should implement these changes.

1) Launch Firefox. Type about:config in the location bar.
2) In the search bar that comes up, enter: security.tls.version.min. Double-click on the entry that appears and change the value to 0.
3) Do the same for security.tls.version.fallback-limit.
4) Try to connect to your site. It should now work for you.

Enable SSL in Java (it has been disabled for a few rev’s now)
1) Open Windows explorer and browse to either (or both if you have x32/x64 bit Java installed):

C:\Program Files (x86)\Java\jre1.8.0_45\lib\security
C:\Program Files\Java\jre1.8.0_45\lib\security

2) Double-click the file named java.security. You will be prompted to select a program to open the file. Choose select a program from a list of installed programs and click OK. Choose either Wordpad or notepad.

3) Scroll down to the bottom of the file. You should see:
jdk.tls.disabledAlgorithms=SSLv3

4) Change this by back-spacing over SSLv3 and save the file so it looks like:
jdk.tls.disabledAlgorithms=

You should now be able to access legacy sites with Java SSL support.