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CVE coverage

CVE-2026-105242

CVSS 5.3 no coverage
View on NVD →
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.

Detection rules

No detection found — yet
None of Sigma, Elastic, Splunk ESCU, YARA, Microsoft Sentinel, Snort, or Suricata currently has a rule referencing CVE-2026-105242.