Apache Log4j JDBCAppender Vulnerability

Apache Log4j JDBCAppender Vulnerability

A critical* Log4j JDBCAppender vulnerability with a CVSS V3.1 Score of 9.8 has been released.

By design, the JDBCAppender in Log4j 1.2.x accepts an SQL statement as a configuration parameter where the values to be inserted are converters from PatternLayout. The message converter, %m, is likely to always be included. This allows attackers to manipulate the SQL by entering crafted strings into input fields or headers of an application that are logged allowing unintended SQL queries to be executed. Note this issue only affects Log4j 1.x when specifically configured to use the JDBCAppender, which is not the default. Beginning in version 2.0-beta8, the JDBCAppender was re-introduced with proper support for parameterized SQL queries and further customization over the columns written to in logs. Apache Log4j 1.2 reached end of life in August 2015.

Affected Systems

The following servers/systems are affected by this vulnerability;

• Apache Log4j 1.2.x

IoC’s

-

Recommended Solution(s)

The following mitigations have been suggested;
1. Upgrade to Log4j Version 2
2. Remove usage of the JDBCAppender from their configurations.

CVE / CWE

CVE-2022-23305

Related Website(s)

• https://nvd.nist.gov/vuln/detail/CVE-2022-23305
• https://www.openwall.com/lists/oss-security/2022/01/18/4
• https://lists.apache.org/thread/pt6lh3pbsvxqlwlp4c5l798dv2hkc85y
• https://logging.apache.org/log4j/1.2/index.html

* Vulnerabilities with a CVSS 3.1 score between 7.0 and 8.9 are evaluated to be “high” whereas vulnerabilities with a CVSS 3.1 score between 9.0 and 10.0 are evaluated to be “critical”.