Package Instance

Deserialization of Untrusted Data in Log4j 1.x
JMSSink in all versions of Log4j 1.x is vulnerable to deserialization of untrusted data when the attacker has write access to the Log4j configuration or if the configuration references an LDAP service the attacker has access to. The attacker can provide a TopicConnectionFactoryBindingName configuration causing JMSSink to perform JNDI requests that result in remote code execution in a similar fashion to CVE-2021-4104. Note this issue only affects Log4j 1.x when specifically configured to use JMSSink, which is not the default. Apache Log4j 1.2 reached end of life in August 2015. Users should upgrade to Log4j 2 as it addresses numerous other issues from the previous versions.

Deserialization of Untrusted Data
JMSAppender in Log4j is vulnerable to deserialization of untrusted data when the attacker has write access to the Log4j configuration. The attacker can provide `TopicBindingName` and `TopicConnectionFactoryBindingName` configurations causing JMSAppender to perform JNDI requests that result in remote code execution in a similar fashion to CVE-2021-44228. Note this issue only affects Log4j when specifically configured to use JMSAppender, which is not the default. Apache Log4j reached end of life in August Users should upgrade to Log4j 2 as it addresses numerous other issues from the previous versions.

Incomplete fix for Apache Log4j vulnerability
The fix to address [CVE-2021-44228](https://nvd.nist.gov/vuln/detail/CVE-2021-44228) in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. This could allow attackers with control over Thread Context Map (MDC) input data when the logging configuration uses a non-default Pattern Layout with either a Context Lookup (for example, $${ctx:loginId}) or a Thread Context Map pattern (%X, %mdc, or %MDC) to craft malicious input data using a JNDI Lookup pattern resulting in a remote code execution (RCE) attack.

Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
By design, the JDBCAppender in Log4j 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 when specifically configured to use the JDBCAppender, which is not the default. Beginning, the JDBCAppender was re-introduced with proper support for parameterized SQL queries and further customization over the columns written to in logs. Apache Log4j reached end of life in August Users should upgrade to Log4j 2 as it addresses numerous other issues from the previous versions.