AS-2021-001: Log4Shell (Log4j 2)

2021-12-16

Statement

None of ASUSTOR's products are affected by CVE-2021-44228, this vulnerability issue only affects software equipped with log4j 2.

Detail

• CVE-2021-44228
  • Severity: Not affected
  • Apache Log4j2 2.0-beta9 through 2.12.1 and 2.13.0 through 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, 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.
• CVE-2021-45046
  • Severity: Not affected
  • It was found that the fix to address CVE-2021-44228 in Apache Log4j 2.15.0 was incomplete in certain non-default configurations. This could allows 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 denial of service (DOS) attack. Log4j 2.15.0 makes a best-effort attempt to restrict JNDI LDAP lookups to localhost by default. Log4j 2.16.0 fixes this issue by removing support for message lookup patterns and disabling JNDI functionality by default.
• CVE-2021-44832
  • Severity: Not affected
  • Apache Log4j2 versions 2.0-beta7 through 2.17.0 (excluding security fix releases 2.3.2 and 2.12.4) are vulnerable to a remote code execution (RCE) attack when a configuration uses a JDBC Appender with a JNDI LDAP data source URI when an attacker has control of the target LDAP server. This issue is fixed by limiting JNDI data source names to the java protocol in Log4j2 versions 2.17.1, 2.12.4, and 2.3.2.

Reference

• CVE-2021-44228
• CVE-2021-45046
• CVE-2021-44832
• Apache Log4j Security Vulnerabilities
• Apache Releases Log4j Version 2.15.0 to Address Critical RCE Vulnerability Under Exploitation

Revision