Apache Log4cxx: Improper HTML escaping in HTMLLayout_CVE-2025-54812

2.1 / 10

LOW

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

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.

Basic Information

ID CVE-2025-54812

Source apache

Published Aug 22, 2025 at 18:46

Modified Aug 22, 2025 at 19:07

Affected Product

Vendor Apache Software Foundation

Product Apache Log4cxx

Affected Versions Apache Software Foundation Apache Log4cxx 0

CWE Classification

CWE-117

References

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    "published": "2025-08-22T18:46:46.205Z",
    "modified": "2025-08-22T19:07:53.330Z",
    "type": "cve",
    "title": "Apache Log4cxx: Improper HTML escaping in HTMLLayout",
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    "references": "https://logging.apache.org/security.html#CVE-2025-54812\nhttps://github.com/apache/logging-log4cxx/pull/509\nhttps://github.com/apache/logging-log4cxx/pull/514",
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