5.3
Medium
CVE-2026-105239 Improper Neutralization of Null Byte or NUL Character vulnerability in the EventLogAppender of Apache log4net
Description
Improper Neutralization of Null Byte or NUL Character vulnerability in the EventLogAppender of Apache log4net. A NUL character in logged content ended the Windows Event Log record at that point, so everything the layout rendered after it, including exception text and trailing fields, was silently not stored. A party whose data reaches a log message could hide the rest of that record. Only applications on Windows that use EventLogAppender are affected. This issue affects Apache log4net: from 1.2.9 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Apache Log4net | Versions not published |
References
- github.com github.com
- github.com github.com
- lists.apache.org lists.apache.org
Timeline
- Published
- Last modified
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