CVE-2026-105242 (GCVE-0-2026-105242)

Vulnerability from cvelistv5 – Published: 2026-10-06 19:50 – Updated: 2026-10-06 19:50
VLAI
Title
Apache log4net: Request validation failure drops the event in the aspnet-request converter
Summary
Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A sender could suppress the log record of their own request. Only applications on ASP.NET for .NET Framework whose layout uses %aspnet-request are affected. This issue affects Apache log4net: from 1.2.11 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-755 - Improper Handling of Exceptional Conditions
Assigner
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache log4net Affected: 1.2.11 , < 3.5.0 (semver)
guessed Create a notification for this product.
Apache Software Foundation Apache log4net Affected: 243f1e9f3ee235955bade4b4fe664a903378719a , < 145203420c579a703008b4b723b6a080757f4964 (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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