CVE-2021-45046 Vulnerability: Analysis, Impact, Mitigation
This requires local or already-authenticated access to exploit.
This requires local or already-authenticated access to reach.
CVE-2021-45046 is a Remote Code Execution (RCE) vulnerability connected to the widely-used Apache Log4j logging library, which allows attackers to manipulate logging data.
CVE-2021-45046 was disclosed on December 14, 2021, following the initial CVE-2021-44228 (Log4Shell) vulnerability.
The flaw was identified during the response to the first issue, with contributions from Apache maintainers and security researchers.
Exploitation attempts were rapidly observed in the wild after disclosure, targeting enterprise software and internal applications using Log4j.
Organizations should scan systems for Log4j versions 2.0-beta9 to 2.15.0 and implement host-based monitoring for anomalous process activities.
To mitigate this vulnerability, update to Log4j version 2.16.0 or later immediately.
What an attacker actually gains: successful exploitation allows the attacker to execute code with the permissions of the affected process.
Initially perceived as a denial-of-service risk, it was later revealed to enable attackers to execute arbitrary code in certain non-default configurations, making it highly critical.
This flaw allows adversaries to escalate access and execute arbitrary code.
This is tracked as CVE-2021-45046 and rated critical severity, which is the identifier to use when checking vendor guidance.
The affected versions are 2.0, so that's the range to check against your own deployment.
The vulnerability stems from improper handling of Java Naming and Directory Interface (JNDI) lookups in Log4j.
Exploits occur when attackers craft malicious log messages containing specially formatted data that bypass initial mitigations.
Disable vulnerable features and monitor systems actively for compromise until vendor recommendations are implemented.
No exploitation has been reported yet, but that status can change, so keep watching vendor guidance while you remediate.
Monitor for irregular JNDI requests, unexpected inbound connections from untrusted IPs, or abnormal execution of Java processes.
What happened
This requires local or already-authenticated access to exploit.
CVE-2021-45046 is a Remote Code Execution (RCE) vulnerability associated with the widely used Apache Log4j logging library, allowing attackers to manipulate logging data.
What changed
CVE-2021-45046 was disclosed on December 14, 2021, following the initial CVE-2021-44228 (Log4Shell) vulnerability.
The flaw was identified during the response to the first issue, with contributions from Apache maintainers and security researchers.
Exploitation attempts were quickly observed in the wild after disclosure, targeting enterprise software and internal applications that utilize Log4j.
Who is affected
Organizations should scan systems for Log4j versions 2.0-beta9 to 2.15.0 and implement host-based monitoring for unusual process activities.
To mitigate this vulnerability, it is crucial to update to Log4j version 2.16.0 or later immediately.
Why it matters
Successful exploitation allows an attacker to execute code with the permissions of the affected process.
Initially perceived as a denial-of-service risk, it was later revealed to enable attackers to execute arbitrary code in certain non-default configurations, making it highly critical.
This flaw allows adversaries to escalate access and execute arbitrary code.
Technical details
This vulnerability is tracked as CVE-2021-45046 and rated as critical severity, which should be referenced when checking vendor guidance.
The affected version is 2.0, so that is the range to verify against your own deployment.
The vulnerability results from improper handling of Java Naming and Directory Interface (JNDI) lookups in Log4j.
Response
Exploits occur when attackers craft malicious log messages containing specially formatted data that bypass initial mitigations.
It is essential to disable vulnerable features and actively monitor systems for signs of compromise until vendor recommendations are followed.
What security teams should do
Monitor for irregular JNDI requests, unexpected inbound connections from untrusted IPs, or abnormal execution of Java processes.