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149 indicators in this extension
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What our analysis found
MailFail is not yet reviewed by Extension Auditor. It comes from a publisher with 14 extensions and was last updated in March 2025.
MailFail Firefox extension security report
ID: mailfail
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149 indicators in this extension
Every finding is verified by a security analyst. Unlock the code evidence, indicators and version history.
About this extension
MailFail identifies and provides commands to exploit a large number of email-related misconfigurations for the current domain and subdomain. The extension's UI popup highlights any misconfigurations in red and links to supporting documentation.
Read the publisher’s full description
<strong>Code</strong> This addon is free and open-source software (FOSS) all code can be found here: <a href="https://prod.outgoing.prod.webservices.mozgcp.net/v1/c234c008eabd4a143685685ce456a65982e312bdc42c2c6d36c6d19406f4db59/https%3A//github.com/ACK-J/MailFail" rel="nofollow">https://github.com/ACK-J/MailFail</a> Please report your bugs or feature requests in a GitHub issue instead of in a review. <strong>Test if it works!</strong> <a href="https://prod.outgoing.prod.webservices.mozgcp.net/v1/efb4f62c334caa0709e7e255c0b8f05a35dc47fe758898ec9d2829051161c87b/https%3A//www.blackhillsinfosec.com/mailfail/" rel="nofollow">https://www.blackhillsinfosec.com/mailfail/</a> <strong>This addon checks misconfigurations with the following protocols:</strong> * SPF * DMARC * DKIM * ARC * BIMI * MX * MTA-STS * DANE * DNSSEC * SMTP TLS Reporting * ADSP * Mail Channels * NSEC * NSEC3 * SRV * Click <a href="https://prod.outgoing.prod.webservices.mozgcp.net/v1/3c2a813d21e419bdf84e511bc78d039d88b972521aa82da56fe9f1f5c19bddb8/https%3A//github.com/ACK-J/MailFail/tree/main%3Ftab=readme-ov-file%23what-misconfigurations-are-checked" rel="nofollow">HERE</a> to read the specifics. <strong>Why I wrote this addon?</strong> While researching email security for a few months I realized that there was a lot of nuance in how different email security protocols worked. It was very confusing at times and I wanted to organize all the different edge cases into a single tool that could help others identify these misconfigurations without having to read through dozens of RFCs. This extension was supposed to be 100 lines of code written in an afternoon, instead it has reached almost 2,000 lines of code over multiple months. <strong>Donations</strong> <ul><li>Monero Address: <strong>89jYJvX3CaFNv1T6mhg69wK5dMQJSF3aG2AYRNU1ZSo6WbccGtJN7TNMAf39vrmKNR6zXUKxJVABggR4a8cZDGST11Q4yS8</strong></li></ul> <strong>Permissions Needed</strong> <strong>Display notifications to you</strong> * This is needed so the addon can alert you when a severe misconfiguration is discovered. <strong>Access browser tabs</strong> * This is needed so the addon can display the proper number of misconfigurations on a per-tab basis. <strong>Privacy Warning</strong> <ul><li>This extension does not use your computers default DNS and instead uses CloudFlare's 1.1.1.1 over DoH. It also uses duckduckgo's icon API to privately retrieve websites favicon images.</li></ul>
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149 indicators in this extension
Every finding is verified by a security analyst. Unlock the code evidence, indicators and version history.
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