The latest update released by Mozilla for Firefox patches a vulnerability that can be exploited to bypass the master password of the built-in password manager and obtain stored passwords.
The flaw, classified as “moderate impact” and tracked as CVE-2019-11733, was patched on Wednesday with the release of Firefox 68.0.2.
Users can set a master password for the password manager built into Firefox to ensure that the saved login information cannot be accessed by unauthorized users. When they access the Saved Logins menu, users have to press the “Show Passwords” button to see the passwords and they have to enter the master password if one has been set.
However, Mozilla learned that users could simply right-click on an entry and select “Copy Password” and the password would be copied to the clipboard without having to enter the master password.
The latest Firefox update addresses the issue and users are now prompted to enter the master password if they use the “Copy Password” option.
“Mozilla rates this fix as ‘moderate’ – after all, it doesn’t let just anyone extract web passwords any time from anywhere – but if you are a Firefox user, it’s worth checking that you are up-to-date,” said Sophos’ Paul Ducklin in a blog post.
One other problem highlighted by Ducklin is that the password manager is turned on by default in Firefox, but users are not required to set a master password by default.
“In other words, a default Firefox setup essentially suffers from the bug described in this article all the time, because there’s no master password used by default, and therefore you never need to enter one,” the expert said.
Related: Mac Malware Delivered via Firefox Exploits Analyzed
Related: Firefox Update to Address Antivirus TLS Errors
Related: Mozilla Bans Firefox Extensions Containing Obfuscated Code