As its name implies, IMAP allows you to **access your email messages wherever you are**; much of the time, it is accessed via the Internet. Basically, email **messages are stored on servers**. Whenever you check your inbox, your email client contacts the server to connect you with your messages. When you read an email message using IMAP, **you aren't actually downloading** or storing it on your computer; instead, you are **reading it off of the server**. As a result, it's possible to check your email from **several different devices** without missing a thing.
By default, the IMAP protocol works on two ports:
* **Port 143** - this is the default IMAP non-encrypted port
* **Port 993** - this is the port you need to use if you want to connect using IMAP securely
```text
PORT STATE SERVICE REASON
143/tcp open imap syn-ack
```
## Banner grabbing
```bash
nc -nv <IP> 143
openssl s_client -connect <IP>:993 -quiet
```
### NTLM Auth - Information disclosure
If the server supports NTLM auth \(Windows\) you can obtain sensitive info \(versions\):
```text
root@kali: telnet example.com 143
* OK The Microsoft Exchange IMAP4 service is ready.
Basic navigation is possible with [CURL](https://ec.haxx.se/usingcurl/usingcurl-reademail#imap), but the documentation is light on details so checking the [source](https://github.com/curl/curl/blob/master/lib/imap.c) is recommended for precise details.
The mail index will be the same index returned from the search operation.
It is also possible to use `UID` \(unique id\) to access messages, however it is less conveniant as the search command needs to be manually formatted. E.g.
Also, possible to download just parts of a message, e.g. subject and sender of first 5 messages \(the `-v` is required to see the subject and sender\):
As its name implies, IMAP allows you to access your email messages wherever you are; much of the time, it is accessed via the Internet. Basically, email messages are stored on servers. Whenever you check your inbox, your email client contacts the server to connect you with your messages. When you read an email message using IMAP, you aren't actually downloading or storing it on your computer; instead, you are reading it off of the server. As a result, it's possible to check your email from several different devices without missing a thing.