Log4Shell JNDI Payload Injection Attempt
The following analytic identifies attempts to inject Log4Shell JNDI payloads via web calls. It leverages the Web datamodel and uses regex to detect patterns like `${jndi:ldap://` in raw web event data, including HTTP…
Description
The following analytic identifies attempts to inject Log4Shell JNDI payloads via web calls. It leverages the Web datamodel and uses regex to detect patterns like `${jndi:ldap://` in raw web event data, including HTTP headers. This activity is significant because it targets vulnerabilities in Java web applications using Log4j, such as Apache Struts and Solr. If confirmed malicious, this could allow attackers to execute arbitrary code, potentially leading to full system compromise. Immediate investigation is required to determine if the attempt was successful and to mitigate any potential exploitation.
Detection logic
Detection requirements
- Platform
- ContainersESXiIaaSLinuxmacOSNetwork DevicesWindows
The rule states no platform. This is derived from the 2 ATT&CK techniques it maps to.
- Log source category
- nginx_access
Known benign triggers
- If there is a vulnerablility scannner looking for log4shells this will trigger, otherwise likely to have low false positives.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| www.lunasec.io/docs/blog/log4j-zero-day/ | 6from 2 sources |
From the source
- At source
- Open at source
- Upstream identifier
- c184f12e-5c90-11ec-bf1f-497c9a704a72
- Tagged by the source as
- CISA AA22-257ACISA AA22-320ALog4Shell CVE-2021-44228EndpointwebSplunk CloudSplunk EnterpriseSplunk Enterprise Securitythreat
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Sep 22, 2026
- Version
- 2