CVE-2021-44832
Log4j JDBC Appender RCE: stopped at runtime
Waratek RASP already blocks this exploit at runtime, inside the JVM - with no application change, no vendor patch, and no downtime.
Published December 28, 2021 · Updated March 4, 2026
The vulnerability
Remote code execution via JDBC Appender JNDI lookup
Log4j configurations that use a JDBC Appender with a JNDI LDAP data source URI let an attacker who controls the target LDAP server return a malicious reference. When the appender resolves that data source, Log4j loads and executes attacker-supplied code, giving remote code execution even after the earlier Log4Shell fixes.
Running an affected version? We can help.
Waratek RASP shields the vulnerable code in production - the exploit is blocked at runtime with no library upgrade, no redeploy, and no downtime. We can have you covered fast.
How Waratek RASP stops it
Blocked at runtime by Waratek RASP
Waratek RASP ships a patch rule that blocks exploitation at the exact point the dangerous operation is attempted, inside the JVM.
Runtime, not perimeter
Waratek RASP acts inside the JVM at the exact call that turns input into code, so obfuscated and encoded payloads are caught where a WAF misses them.
No code changes
Protection is applied as a rule at runtime. No source edits, no recompilation, no library upgrade, and no application restart required.
Zero false positives
Rules target the specific unsafe behaviour of the exploit, so legitimate traffic keeps flowing while the attack is blocked and logged.
| Mod | Rules | Enable |
|---|---|---|
| Log4j JDBC Appender RCE protectionCVE-2021-44832 · Improper input validation (JNDI data source URI) | 1 | |
| SQL Injection protectionQuery manipulation | 4 | |
| Path Traversal protectionUnsafe file access | 3 |
Flip one toggle in the Waratek Portal. The protection deploys to every attached application, with no restart.
Common questions
Log4j JDBC Appender RCE FAQ
Is Log4j JDBC Appender RCE (CVE-2021-44832) exploitable?
CVE-2021-44832 carries a CVSS 6.6/10 (MEDIUM) rating and affects Apache Log4j 2 (log4j-core) 2.0-beta7 through 2.17.0 (excluding 2.3.2 and 2.12.4). Log4j configurations that use a JDBC Appender with a JNDI LDAP data source URI let an attacker who controls the target LDAP server return a malicious reference. When the appender resolves that data source, Log4j loads and executes attacker-supplied code, giving remote code execution even after the earlier Log4Shell fixes.
How does Waratek mitigate Log4j JDBC Appender RCE (CVE-2021-44832)?
Waratek RASP blocks exploitation of Log4j JDBC Appender RCE (CVE-2021-44832) inside the JVM at runtime, with no application code changes, no vendor patch and no restart.
How quickly was Log4j JDBC Appender RCE (CVE-2021-44832) exploited after disclosure?
A working exploit for CVE-2021-44832 appeared within 2 days of its NVD disclosure, on December 29, 2021.
Protect your apps in production
Get protected against Log4j JDBC Appender RCE - without code changes or redeploying
Book a call and we’ll show you how Waratek RASP shields your running applications against CVE-2021-44832 and attacks like it, and get you covered in production.