Firefox, Tor Disables Extensions due to Certificate Expiration
|by Alpha Team
On May 3 2019, users on a Firefox thread started complaining that add-ons on the latest version of Firefox stopped working. On May 4, Firefox released a new version that fixed the bug, with a blog post describing the incident. In the post, the Firefox team failed to renew an intermediate certificate which caused addons to stop working. This subsequently affected the Tor browser, which caused the popular Noscript addon to fail, significantly increasing the risk of Tor browser users.
Recommendations
- Upgrade to the latest version of Firefox - 66.0.4 on Desktop/Android and 60.6.2 for ESR
- If you are a Tor user, wait for an update so security addons like Noscript are re-enabled
- Enable the Cyber Attack Chatter rule in the platform and configure it to listen for additional news related to this story
Details
As of 6 May 2019, the thread for the bug has reached approximately 300 replies of users complaining. The browser does not allow unsigned add-ons by default - so when the intermediate certificate expired, users were locked out of their extensions. The workarounds posted on the thread and throughout social media mentioned disabling extension signature verification, which significantly increases the risk of malicious add-ons to the Mozilla browser.
Tags: dark web, all industries, global