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.

Some siimple checks to see if JAR file is vulnerable to CVE-2021-44228

### chk_log4j - Tool to find jar files which are vulnerable to log4j CVE-2021-44228.


#### Install

1. `git clone https://github.com/gcmurphy/chk_log4j`
2. `cd chk_log4j && cargo install --path .`


#### Usage

The tool only checks a single file so it is best combined with something like [fd](https://github.com/sharkdp/fd).

```
$ fd -a -e jar -x chk_log4j
```

 [4.0K]  /data/pocs/9ae8f9389d26d8828a8d143393c540edf4d05fab
├── [ 11K]  Cargo.lock
├── [ 518]  Cargo.toml
├── [ 365]  README.md
├── [4.0K]  src
│   └── [3.0K]  main.rs
└── [2.7K]  vulnerable.sha256

1 directory, 5 files