# 110,995 - Pentesting POP

{{#include ../banners/hacktricks-training.md}}

## 基本信息

**邮局协议 (POP)** 被描述为计算机网络和互联网领域中的一种协议，用于从远程邮件服务器中提取和**检索电子邮件**，使其在本地设备上可访问。该协议位于OSI模型的应用层，使用户能够获取和接收电子邮件。**POP客户端**的操作通常涉及与邮件服务器建立连接，下载所有消息，将这些消息存储在客户端系统上，然后从服务器中删除它们。尽管该协议有三个版本，但**POP3** 是最常用的版本。

**默认端口：** 110, 995(ssl)
```
PORT    STATE SERVICE
110/tcp open  pop3
```
## 枚举

### 横幅抓取
```bash
nc -nv <IP> 110
openssl s_client -connect <IP>:995 -crlf -quiet
```
## 手动

您可以使用命令 `CAPA` 来获取 POP3 服务器的功能。

## 自动化
```bash
nmap --script "pop3-capabilities or pop3-ntlm-info" -sV -port <PORT> <IP> #All are default scripts
```
`pop3-ntlm-info` 插件将返回一些 "**敏感**" 数据（Windows 版本）。

### [POP3 暴力破解](../generic-hacking/brute-force.md#pop)

## POP 语法

POP 命令示例来自 [这里](http://sunnyoasis.com/services/emailviatelnet.html)
```bash
POP commands:
USER uid           Log in as "uid"
PASS password      Substitue "password" for your actual password
STAT               List number of messages, total mailbox size
LIST               List messages and sizes
RETR n             Show message n
DELE n             Mark message n for deletion
RSET               Undo any changes
QUIT               Logout (expunges messages if no RSET)
TOP msg n          Show first n lines of message number msg
CAPA               Get capabilities
```
示例：
```
root@kali:~# telnet $ip 110
+OK beta POP3 server (JAMES POP3 Server 2.3.2) ready
USER billydean
+OK
PASS password
+OK Welcome billydean

list

+OK 2 1807
1 786
2 1021

retr 1

+OK Message follows
From: jamesbrown@motown.com
Dear Billy Dean,

Here is your login for remote desktop ... try not to forget it this time!
username: billydean
password: PA$$W0RD!Z
```
## 记录密码

启用 **`auth_debug`** 设置的 POP 服务器将增加生成的日志。然而，如果 **`auth_debug_passwords`** 或 **`auth_verbose_passwords`** 设置为 **`true`**，密码也可能以明文形式记录在这些日志中。

## HackTricks 自动命令
```
Protocol_Name:  POP   #Protocol Abbreviation if there is one.
Port_Number:  110     #Comma separated if there is more than one.
Protocol_Description: Post Office Protocol         #Protocol Abbreviation Spelled out

Entry_1:
Name: Notes
Description: Notes for POP
Note: |
Post Office Protocol (POP) is described as a protocol within the realm of computer networking and the Internet, which is utilized for the extraction and retrieval of email from a remote mail server**, making it accessible on the local device. Positioned within the application layer of the OSI model, this protocol enables users to fetch and receive email. The operation of POP clients typically involves establishing a connection to the mail server, downloading all messages, storing these messages locally on the client system, and subsequently removing them from the server. Although there are three iterations of this protocol, POP3 stands out as the most prevalently employed version.

https://book.hacktricks.wiki/en/network-services-pentesting/pentesting-pop.html

Entry_2:
Name: Banner Grab
Description: Banner Grab 110
Command: nc -nv {IP} 110

Entry_3:
Name: Banner Grab 995
Description: Grab Banner Secure
Command: openssl s_client -connect {IP}:995 -crlf -quiet

Entry_4:
Name: Nmap
Description: Scan for POP info
Command: nmap --script "pop3-capabilities or pop3-ntlm-info" -sV -p 110 {IP}

Entry_5:
Name: Hydra Brute Force
Description: Need User
Command: hydra -l {Username} -P {Big_Passwordlist} -f {IP} pop3 -V

Entry_6:
Name: consolesless mfs enumeration
Description: POP3 enumeration without the need to run msfconsole
Note: sourced from https://github.com/carlospolop/legion
Command: msfconsole -q -x 'use auxiliary/scanner/pop3/pop3_version; set RHOSTS {IP}; set RPORT 110; run; exit'

```
{{#include ../banners/hacktricks-training.md}}