Apache Log4j Log4Shell (CVE-2021-44228) RCE Vulnerability Analysis, POC, and Mitigation

Vulnerability Summary Vulnerability Overview Vulnerability Name: Apache Log4j Remote Code Execution Vulnerability (Log4Shell) Vulnerability ID: CVE-2021-44228 Vulnerability Type: Remote Code Execution (RCE) Vulnerability Description: Apache Log4j 2 contains a vulnerability when parsing JNDI log messages. Attackers can trigger JNDI injection by crafting malicious log messages, thereby executing arbitrary code on the target server. Vulnerability Mechanism: Attackers exploit the JNDI feature of Log4j by crafting log messages containing malicious protocols such as LDAP or RMI, inducing Log4j to load and execute malicious class files from remote servers. Affected Scope Affected Versions: - Apache Log4j 2.0-beta9 through 2.14.1 (inclusive) - Some versions of 2.15.0 (requires specific configurations) Affected Products: - Java applications using Log4j 2 - Middleware, frameworks, and libraries containing Log4j 2 (e.g., Spring Boot, Apache Kafka, Apache Flink, etc.) - Cloud services and SaaS platforms (if they rely on Log4j 2 at the underlying level) Remediation Official Patched Versions: - Upgrade to Log4j 2.17.1 or higher (Recommended) - If immediate upgrade is not possible, temporarily disable the JNDI feature (see Temporary Mitigation Measures below) Temporary Mitigation Measures: 1. Set system property: 2. Remove the class (applicable to Log4j 2.10.0 through 2.14.1): 3. Disable JNDI in : POC Code / Exploit Code > ⚠️ Note: The code above is for demonstration purposes only. Actual attacks require coordination with malicious LDAP/RMI servers and class files. Do not use for illegal purposes. Other Key Information Discovery Date: December 2021 Disclosure Date: December 10, 2021 Vulnerability Rating: CVSS v3.1 Score 10.0 (Critical) Impact: Can lead to complete server compromise, data leakage, DDoS attacks, etc. Remediation Recommendations: - Immediately upgrade Log4j to version 2.17.1 or higher. - Inspect all components dependent on Log4j 2. - Monitor network traffic for anomalous JNDI requests. - Implement the principle of least privilege to restrict server access permissions.

Goal Reached Thanks to every supporter — we hit 100%!

Apache Log4j Log4Shell (CVE-2021-44228) RCE Vulnerability Analysis, POC, and Mitigation

More from this source