SB2021121504 - Improper input validation in Apache Log4j



SB2021121504 - Improper input validation in Apache Log4j

Published: December 15, 2021 Updated: April 14, 2025

Security Bulletin ID SB2021121504
Severity
High
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Code Injection (CVE-ID: CVE-2021-45046)

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to incomplete patch in Apache Log4j 2.15.0 for a code injection vulnerability #VU58816 (CVE-2021-44228) in certain non-default configurations. A remote attacker 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) can pass malicious data using a JNDI Lookup pattern and perform a denial of service (DoS) attack, exfiltrate data or execute arbitrary code.

Later discovery demonstrates a remote code execution on macOS but no other tested environments.


Remediation

Install update from vendor's website.