BlueLight: A Firefox extension for Notification of SSL Monitoring


BlueLight provides user notification of SSL/TLS inspection based on certificates known to be associated with SSL inspection, usually by implementing an SSL MitM using organizational PKI.
The intuition behind BlueLight is that it can be reassuring to know when your secure communications are protected by monitoring. This is analogous to the blue lights often used to call attention to security cameras.


To operate correctly, a regular expression covering the certificates known to be associated with SSL inspection must be configured for the key "extensions.bluelight.inspectioncertregex". This regex is applied to the issuer CN (Issuer or Verified by Common Name).
You can also customize the "Learn More" link by changing the "extensions.bluelight.moreinfourl" key. It is recommended that this be changed to a URL more useful for your organziation. e.g. A link which explains why SSL monitoring is being used and how it protects the user.
These settings are accessed through about:config.
It is expressely permitted and highly recommended that bluelight be repackaged to change the default settings (see prefs.js) or that these be set through customized firefox deployment methods.


You can download the current version (0.0.5 released 2013-10-19) here
You can also download from


BlueLight is based heavily on Cert Alert by chihchun.
BlueLight is licensed under the Mozilla Public License. Alternatively, it can be licensed under GPL or LGPL. See bluelight.js for details.

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