AI-powered email threat detection extension
A browser extension for Gmail and Outlook, co-developed at AMAN Security, that analyzes incoming email in real time with an AI classification model. When a message is flagged, the extension blocks interaction with it until the user acknowledges the warning, and it processes email content without storing or retaining user data.
- Type
- Product (AMAN Security startup), co-developed
- Platforms
- Gmail, Outlook
- Status
- On hold (maintained in production from 2025)
- Key result
- 98% detection accuracy (internal testing)
- Focus
- Phishing links, Spoofed senders, Attachments, BEC / look-alike domains
Problem
Email is still where many attacks start. Phishing links, spoofed senders, malicious attachments and business-email-compromise messages all arrive in the same inbox as legitimate mail, and the final decision to click usually rests with the user, often under time pressure created by the message itself.
The goal was to put a check at the point where that decision is made: inside the mailbox, in real time, as the email is read. That check had to do two things: catch the threat, and stop the user from acting on it by reflex. It also had to do this without keeping a copy of anyone's email.
Architecture & approach
The design follows the moment a user reads an email:
- Analyze in place. The extension runs inside Gmail and Outlook and analyzes incoming email in real time, so the check happens before the user acts.
- Look at several signals, not one. Detection logic covers links, sender domains, attachments and the language of the message itself (see the table below).
- Classify with a model. An AI classification model produces the verdict for each email.
- Interrupt, don't just label. When a threat is detected, interaction with the email is blocked until the warning is acknowledged.
- Keep nothing. Email content is processed without being stored or retained, following privacy-by-design principles.
Detection signals
| Signal | Threat it targets |
|---|---|
| Phishing links | Links that lead to credential-harvesting or malicious pages |
| Spoofed sender domains | Mail claiming to come from a domain it was not sent from |
| Malicious attachments | Files delivered as the payload of the attack |
| Social-engineering language | Wording designed to manipulate the reader into acting |
| Urgency-based language | Artificial time pressure that discourages checking |
| Look-alike / BEC-style domains | Domains imitating a trusted organization or contact (business email compromise) |
What I did
- Co-developed and maintained a browser extension for Gmail and Outlook that analyzes incoming emails in real time using an AI classification model.
- Built detection logic for phishing links, spoofed sender domains, malicious attachments, social-engineering and urgency-based language, and look-alike or BEC-style domains.
- Implemented protective controls that block user interaction with detected threats until the warning is acknowledged.
- Applied privacy-by-design principles: email content is processed without storing or retaining user data.
- Maintained the system in production from 2025 to protect users against email-based threats.
Tools
| Component | Role in the product |
|---|---|
| Browser extension | Runs in Gmail and Outlook; analyzes incoming email in real time |
| AI classification model | Classifies each email and produces the threat verdict |
| Detection logic | Covers links, sender and look-alike domains, attachments, social-engineering and urgency language |
| Protective controls | Block interaction with a flagged email until the warning is acknowledged |
Result
98% detection accuracy in internal testing of the classification model, with the extension maintained in production from 2025 to protect users against email-based threats. The AMAN Security project is currently on hold.
Lessons learned
- A warning has to interrupt to work. Blocking interaction until the warning is acknowledged puts a deliberate pause between the user and the risky action.
- Phishing is more than a bad link. Spoofed senders, look-alike domains and urgent, manipulative wording each need their own detection, and they often appear together.
- Privacy is a design constraint, not a feature. Deciding up front not to store or retain email content shaped how the system could be built and maintained.
- A test score is a starting point. 98% in internal testing is a measurement on a specific test set; running the system in production is what shows how it holds up.