CVE-2021-4104
HIGH EXPLOITEDApache Log4j 1.2 - Remote Code Execution via JMSAppender JNDI Requests
Title source: llmExploitation Summary
CVE-2021-4104 has been observed exploited in the wild (reported by VulnCheck KEV). EIP tracks 3 public exploits from researchers including cckuailong, JAckLosingHeart, cuijiung.
AI-analyzed exploit summary This repository contains a minimal stub for CVE-2021-4104 (Log4j 1.x RCE) but lacks functional exploit code. The README describes prerequisites (JMS environment and log4j.properties modification) and references Log4Shell 2.x, while the Java file is a basic Log4j logging example without exploitation logic.
Description
JMSAppender in Log4j 1.2 is vulnerable to deserialization of untrusted data when the attacker has write access to the Log4j configuration. The attacker can provide TopicBindingName and TopicConnectionFactoryBindingName configurations causing JMSAppender to perform JNDI requests that result in remote code execution in a similar fashion to CVE-2021-44228. Note this issue only affects Log4j 1.2 when specifically configured to use JMSAppender, which is not the default. Apache Log4j 1.2 reached end of life in August 2015. Users should upgrade to Log4j 2 as it addresses numerous other issues from the previous versions.
Exploits (3)
This repository contains a minimal stub for CVE-2021-4104 (Log4j 1.x RCE) but lacks functional exploit code. The README describes prerequisites (JMS environment and log4j.properties modification) and references Log4Shell 2.x, while the Java file is a basic Log4j logging example without exploitation logic.
The repository contains a minimal Java test file that logs a debug message using Log4j but does not demonstrate any exploit for CVE-2021-4104. It lacks the crafted payload or malicious input required to trigger the vulnerability.
This PoC demonstrates CVE-2021-4104, a Log4j 1.x RCE vulnerability via JMS deserialization. The Evil.java class exploits the vulnerability by executing arbitrary code (calc.exe) when instantiated, while Test.java simulates a vulnerable Log4j 1.x environment.
References (14)
Scores
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H