Apache Log4j < 2.15.0 Remote Code Execution (Nix)

critical Nessus Plugin ID 155999


A package installed on the remote host is affected by a remote code execution vulnerability.


The version of Apache Log4j on the remote host is 2.x < 2.3.1 / 2.4 < 2.12.2 / 2.13 < 2.15.0. It is, therefore, affected by a remote code execution vulnerability in the JDNI parser due to improper log validation. An unauthenticated, remote attacker can exploit this to bypass authentication and execute arbitrary commands.

Log4j 1.x, which reached its End of Life prior to 2016, comes with JMSAppender which will perform a JNDI lookup if enabled in Log4j's configuration file, hence customers should evaluate triggers in 1.x based on the risk that it is EOL and whether JNDI lookups are enabled.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.


Upgrade to Apache Log4j version 2.3.1 / 2.12.2 / 2.15.0 or later, or apply the vendor mitigation.

Upgrading to the latest versions for Apache Log4j is highly recommended as intermediate versions / patches have known high severity vulnerabilities and the vendor is updating their advisories often as new research and knowledge about the impact of Log4j is discovered. Refer to https://logging.apache.org/log4j/2.x/security.html for the latest versions.

See Also



Plugin Details

Severity: Critical

ID: 155999

File Name: apache_log4j_2_15_0.nasl

Version: 1.28

Type: local

Agent: unix

Family: Misc.

Published: 12/10/2021

Updated: 5/20/2024

Configuration: Enable thorough checks

Supported Sensors: Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus

Risk Information


Risk Factor: Critical

Score: 10.0


Risk Factor: High

Base Score: 9.3

Temporal Score: 8.1

Vector: CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2021-44228


Risk Factor: Critical

Base Score: 10

Temporal Score: 9.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:H/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:apache:log4j

Required KB Items: installed_sw/Apache Log4j, Host/local_checks_enabled

Excluded KB Items: SMB/Registry/Enumerated

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 12/9/2021

Vulnerability Publication Date: 12/9/2021

CISA Known Exploited Vulnerability Due Dates: 12/24/2021

Exploitable With


Core Impact

Reference Information

CVE: CVE-2021-44228

IAVA: 0001-A-0650, 2021-A-0573