Severity: low 

Affected versions:

- Apache Log4cxx before 1.5.0

Description:

Improper Output Neutralization for Logs vulnerability in Apache Log4cxx.


When using HTMLLayout, logger names are not properly escaped when writing out 
to the HTML file.
If untrusted data is used to retrieve the name of a logger, an attacker could 
theoretically inject HTML or Javascript in order to hide information from logs 
or steal data from the user.
In order to activate this, the following sequence must occur:



  *  Log4cxx is configured to use HTMLLayout.

  *  Logger name comes from an untrusted string

  *  Logger with compromised name logs a message

  *  User opens the generated HTML log file in their browser, leading to 
potential XSS


Because logger names are generally constant strings, we assess the impact to 
users as LOW


This issue affects Apache Log4cxx: before 1.5.0.


Users are recommended to upgrade to version 1.5.0, which fixes the issue.

Credit:

Sovereign Tech Agency (sponsor)

References:

https://logging.apache.org/security.html#CVE-2025-54812
https://github.com/apache/logging-log4cxx/pull/509
https://github.com/apache/logging-log4cxx/pull/514
https://logging.apache.org/
https://www.cve.org/CVERecord?id=CVE-2025-54812

Reply via email to