Possible Log4Shell JNDI Injection in HTTP Request
- Category
- webserver
- Author
- HuntRule
- Published
- 2026-05-18
- Updated
- 2026-08-28
ATT&CK techniques
Initial AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects JNDI lookup strings in HTTP request URIs or fields, indicative of Log4Shell (CVE-2021-44228) exploitation attempts against Log4j. Attackers embed jndi:ldap, jndi:rmi, or jndi:dns references, often inside headers such as X-Api-Version, to force the vulnerable logger to fetch and execute a remote class.
Reporting behind it
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
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