Improper Output Neutralization for Logs Affecting log4cxx package, versions [,1.5.0)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-CONAN-LOG4CXX-12179275
- published25 Aug 2025
- disclosed22 Aug 2025
- creditUnknown
Introduced: 22 Aug 2025
NewCVE-2025-54812 (opens in a new tab)How to fix?
Upgrade log4cxx to version 1.5.0 or higher.
Overview
Affected versions of this package are vulnerable to Improper Output Neutralization for Logs in the HTMLLayout class. An attacker can execute arbitrary HTML or JavaScript code by injecting malicious content into the logger name, which is then written to the HTML log file and subsequently opened in a user's browser.
Note:
This is only exploitable if the logger name is derived from untrusted input, Log4cxx is configured to use HTMLLayout, and a user opens the generated HTML log file in a browser.