Possible Log4Shell JNDI Exploitation Attempt in Web Request

PremiumReviewedSigma · High · v1
Category
webserver
Author
HuntRule
Published
2026-08-20
Updated
2026-08-28

ATT&CK techniques

Initial Access
  1. Recon

  2. Resource Dev

  3. Execution

  4. Persistence

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. 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.

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Pivot detection · T1190 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.