CVE-2021-44228 PoC — Apache Log4j2 JNDI features do not protect against attacker controlled LDAP and other JNDI related endpoints

Title:Apache Log4j2 JNDI features do not protect against attacker controlled LDAP and other JNDI related endpoints (CVE-2021-44228)
Description:Apache Log4j2 2.0-beta9 through 2.15.0 (excluding security releases 2.12.2, 2.12.3, and 2.3.1) JNDI features used in configuration, log messages, and parameters do not protect against attacker controlled LDAP and other JNDI related endpoints. An attacker who can control log messages or log message parameters can execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled. From log4j 2.15.0, this behavior has been disabled by default. From version 2.16.0 (along with 2.12.2, 2.12.3, and 2.3.1), this functionality has been completely removed. Note that this vulnerability is specific to log4j-core and does not affect log4net, log4cxx, or other Apache Logging Services projects.

CVE-2021-44228 检查工具

#### #1 使用说明

CVE-2021-44228 log4j 2.x rce漏洞检测工具，对目标链接发起get请求并利用dnslog探测是否有回显

```bash
$ python3 log4j-scan.py -h
Usage: python log4j-scan.py -u <target url>

Options:
  -h, --help         show this help message and exit
  -u URL, --url=URL  输入需要检查的链接，如: https://ainrm.cn
```

#### #2 过程截图

1. 内置8个公开payload与18个请求头，共144种组合方式

![ainrm@20211214160504](./tu/ainrm@20211214160504.png)

2. `-u`形式传入链接

![ainrm@20211214162054](./tu/ainrm@20211214162054.png)

 [4.0K]  /data/pocs/8740fd866ec4f9022c2f64d8d65f7d9cbca7f13d
├── [4.7K]  log4j-scan.py
├── [ 588]  README.md
└── [4.0K]  tu
    ├── [720K]  ainrm@20211214160504.png
    └── [213K]  ainrm@20211214162054.png

1 directory, 4 files