CVE-2026-105240 (GCVE-0-2026-105240)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:47 – Updated: 2026-10-06 19:47
VLAI
Title
Apache log4net: NUL character truncates OutputDebugStringAppender records
Summary
Improper Neutralization of Null Byte or NUL Character vulnerability in the OutputDebugStringAppender of Apache log4net. A NUL character in logged content ended the debug output record at that point, so everything the layout rendered after it, including exception text and trailing fields, was silently lost. A party whose data reaches a log message could hide the rest of that record. Only applications on Windows that use OutputDebugStringAppender 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.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-158 - Improper Neutralization of Null Byte or NUL Character
Assigner
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache log4net Affected: 1.2.9 , < 3.5.0 (semver)
guessed Create a notification for this product.
Apache Software Foundation Apache log4net Affected: 02e1e115435888485f2e28b414d267e39e799e07 , < 6046fe9d7f353b49fe995361c071ec2eea8f7ef6 (git)
guessed Create a notification for this product.
Credits
The Apache Software Foundation Claude Security Jan Friedrich
Show details on NVD website
To clipboard 

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