Possible Log4Shell JNDI Exploitation Attempt in Web Request
- Category
- webserver
- Author
- HuntRule
- Published
- 2026-10-17
- Updated
- 2026-10-17
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 Log4Shell exploitation attempts where a JNDI lookup expression is embedded in the request URI or headers including LDAP RMI and DNS callbacks and URL encoded variants as described in NCC Group Log4Shell detection research. Adversaries inject these strings to trigger CVE-2021-44228 remote code execution in vulnerable Log4j components so matching requests indicate active exploitation.
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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