--- title: "Log4Shell CVE-2021-44228" last_modified_at: 2021-12-11 toc: true toc_label: "" tags: - Splunk Enterprise - Splunk Enterprise Security - Splunk Cloud - Endpoint - Network_Traffic - Web --- [Try in Splunk Security Cloud](https://www.splunk.com/en_us/cyber-security.html){: .btn .btn--success} #### Description Log4Shell or CVE-2021-44228 is a Remote Code Execution (RCE) vulnerability in the Apache Log4j library, a widely used and ubiquitous logging framework for Java. The vulnerability allows an attacker who can control log messages to execute arbitrary code loaded from attacker-controlled servers and we anticipate that most apps using the Log4j library will meet this condition. - **Product**: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud - **Datamodel**: [Endpoint](https://docs.splunk.com/Documentation/CIM/latest/User/Endpoint), [Network_Traffic](https://docs.splunk.com/Documentation/CIM/latest/User/NetworkTraffic), [Web](https://docs.splunk.com/Documentation/CIM/latest/User/Web) - **Last Updated**: 2021-12-11 - **Author**: Jose Hernandez - **ID**: b4453928-5a98-11ec-afcd-8de10b48fc52 #### Narrative In late November 2021, Chen Zhaojun of Alibaba identified a remote code execution vulnerability. Previous work was seen in a 2016 Blackhat talk by Alvaro Munoz and Oleksandr Mirosh called ["A Journey from JNDI/LDAP Manipulation to Remote Code Execution Dream Land"](https://www.blackhat.com/docs/us-16/materials/us-16-Munoz-A-Journey-From-JNDI-LDAP-Manipulation-To-RCE.pdf). Reported under the CVE ID : CVE-2021-44228, released to the public on December 10, 2021. The vulnerability is exploited through improper deserialization of user input passed into the framework. It permits remote code execution and it can allow an attacker to leak sensitive data, such as environment variables, or execute malicious software on the target system. #### Detections | Name | Technique | Type | | ----------- | ----------- |--------------| | [Any Powershell DownloadFile](/endpoint/any_powershell_downloadfile/) | [Command and Scripting Interpreter](/tags/#command-and-scripting-interpreter), [PowerShell](/tags/#powershell) | TTP | | [CMD Carry Out String Command Parameter](/endpoint/cmd_carry_out_string_command_parameter/) | [Windows Command Shell](/tags/#windows-command-shell), [Command and Scripting Interpreter](/tags/#command-and-scripting-interpreter) | Hunting | | [Curl Download and Bash Execution](/endpoint/curl_download_and_bash_execution/) | [Ingress Tool Transfer](/tags/#ingress-tool-transfer) | TTP | | [Detect Outbound LDAP Traffic](/network/detect_outbound_ldap_traffic/) | [Exploit Public-Facing Application](/tags/#exploit-public-facing-application), [Command and Scripting Interpreter](/tags/#command-and-scripting-interpreter) | Hunting | | [Hunting for Log4Shell](/endpoint/hunting_for_log4shell/) | [Exploit Public-Facing Application](/tags/#exploit-public-facing-application) | Hunting | | [Java Class File download by Java User Agent](/endpoint/java_class_file_download_by_java_user_agent/) | [Exploit Public-Facing Application](/tags/#exploit-public-facing-application) | TTP | | [Linux Java Spawning Shell](/endpoint/linux_java_spawning_shell/) | [Exploit Public-Facing Application](/tags/#exploit-public-facing-application) | TTP | | [Log4Shell JNDI Payload Injection Attempt](/web/log4shell_jndi_payload_injection_attempt/) | [Exploit Public-Facing Application](/tags/#exploit-public-facing-application) | Anomaly | | [Log4Shell JNDI Payload Injection with Outbound Connection](/web/log4shell_jndi_payload_injection_with_outbound_connection/) | [Exploit Public-Facing Application](/tags/#exploit-public-facing-application) | Anomaly | | [Malicious PowerShell Process - Connect To Internet With Hidden Window](/endpoint/malicious_powershell_process_-_connect_to_internet_with_hidden_window/) | [PowerShell](/tags/#powershell), [Command and Scripting Interpreter](/tags/#command-and-scripting-interpreter) | Hunting | | [Outbound Network Connection from Java Using Default Ports](/endpoint/outbound_network_connection_from_java_using_default_ports/) | [Exploit Public-Facing Application](/tags/#exploit-public-facing-application) | TTP | | [Wget Download and Bash Execution](/endpoint/wget_download_and_bash_execution/) | [Ingress Tool Transfer](/tags/#ingress-tool-transfer) | TTP | | [Windows Java Spawning Shells](/endpoint/windows_java_spawning_shells/) | [Exploit Public-Facing Application](/tags/#exploit-public-facing-application) | TTP | #### Reference * [https://mbechler.github.io/2021/12/10/PSA_Log4Shell_JNDI_Injection/](https://mbechler.github.io/2021/12/10/PSA_Log4Shell_JNDI_Injection/) * [https://www.fastly.com/blog/digging-deeper-into-log4shell-0day-rce-exploit-found-in-log4j](https://www.fastly.com/blog/digging-deeper-into-log4shell-0day-rce-exploit-found-in-log4j) * [https://www.crowdstrike.com/blog/log4j2-vulnerability-analysis-and-mitigation-recommendations/](https://www.crowdstrike.com/blog/log4j2-vulnerability-analysis-and-mitigation-recommendations/) * [https://www.lunasec.io/docs/blog/log4j-zero-day/](https://www.lunasec.io/docs/blog/log4j-zero-day/) * [https://www.splunk.com/en_us/blog/security/log-jammin-log4j-2-rce.html](https://www.splunk.com/en_us/blog/security/log-jammin-log4j-2-rce.html) [*source*](https://github.com/splunk/security_content/tree/develop/stories/log4shell_cve-2021-44228.yml) \| *version*: **1**