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Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection') in cx-dummy-package

CVE-2021-44228

  • cx-dummy-package
  • org.apache.logging.log4j:log4j-core
Severity High
Score 10/10

Summary

Apache Log4j2 in versions 2.0-beta9 prior to 2.3.1, 2.4 prior to 2.12.3, and 2.13.0 prior to 2.15.0 JNDI features used in configuration, log messages, and parameters do not protect against attacker-controlled LDAP and other JNDI-related endpoints. An attacker who can control log messages or log message parameters can execute arbitrary code loaded from LDAP servers when message lookup substitution is enabled. From log4j 2.15.0, this behavior has been disabled by default. From version 2.16.0 (for users requiring Java 8 or later), 2.12.3 (for Java 7 users), and 2.3.1 (for Java 6 users) this functionality has been completely removed. Note that this vulnerability is specific to log4j-core and does not affect log4net, log4cxx, or other Apache Logging Services projects. ### How to remediate the Log4j RCE vulnerability? ### The easiest and most recommended way to remediate this vulnerability is to [update to log4j version 2.17.0 or later](https://logging.apache.org/log4j/2.x/download.html). If updating the package is an issue, you may remove the JndiLookup class from the classpath. The command to perform such action is: `zip -q -d log4j-core-*.jar org/apache/logging/log4j/core/lookup/JndiLookup.class`.

  • LOW
  • NETWORK
  • HIGH
  • CHANGED
  • NONE
  • NONE
  • HIGH
  • HIGH

CWE-917 - Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection')

The software constructs all or part of an expression language (EL) statement in a framework such as a Java Server Page (JSP) using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended EL statement before it is executed.

Advisory Timeline

  • Published