Windows XP and Vista users get Firefox 43.0 offered because of signing issues of the Firefox installer.

Current Firefox release on the CDN server:

• http://download.cdn.mozilla.net/pub/firefox/releases/44.0/

See also this SUMO knowledge base article that needs an update.

• https://support.mozilla.org/en-US/kb/get-latest-version-firefox-windows-xp-vista

• https://blog.mozilla.org/security/2016/01/06/man-in-the-middle-interfering-with-increased-security/

also refer to How can I get the latest version of Firefox on Windows XP or Vista?

Thanks. Ok via autoupdate. I hope only for ff44, then from ff44 to ff45 I will be able to donwnload ok? thanks a lot. best,

the same issue with ff45! signing issue again? even for future releases will I have to upgrade FF via autoupdate?

How to tell if you’re affected: https://blog.mozilla.org/security/2016/01/06/man-in-the-middle-interfering-with-increased-security/

test result: I am NOT affected.

thanks.

Firefox 43.0.2 to current Firefox 45.0 on Windows is still signed.

Not every Windows Vista users keep their system updated with patches like https://support.microsoft.com/en-us/kb/2763674 for various reasons either due to not bothering or perhaps a pirated copy.

WinXP users who have SP2 and not SP3 cannot install 43.0.2 and newer setups.

Mozilla choose to serve a working version (43.0.1) that users can update from instead of a version many users cannot install.

If you do have a updated Vista system then you can install Firefox 45.0 https://ftp.mozilla.org/pub/firefox/releases/45.0.2/win32/

edit changed link from 45.0 to 45.0.2 since thread was bumped. Firefox 46.0 is scheduled for Release on April 26.

edit.