Possible Log4Shell JNDI Exploitation Attempt in Web Request
- Category
- webserver
- Author
- HuntRule
- Published
- 2026-08-20
- 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 Log4Shell (CVE-2021-44228) exploitation strings such as JNDI LDAP/RMI/DNS lookups and Log4j lookup obfuscation appearing in web request URIs and User-Agent headers. Attackers embed these expressions to force vulnerable Log4j2 loggers into resolving attacker-controlled JNDI references, leading to remote code execution.
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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