Riskcovery

CVE-2026-105242

Apache log4net: Request validation failure drops the event in the aspnet-request converter

State
Published
Severity
5.3 Medium
Published
Oct 6, 2026
Updated
Oct 7, 2026
Reserved
Oct 4, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
3.15.3 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Napache

Weaknesses

  • CWE-755 Improper Handling of Exceptional Conditions

Affected Products

ProductVersions
Apache log4netApache Software Foundation
  • 1.2.11 to before 3.5.0Affected
Apache log4netApache Software Foundation
  • 243f1e9f3ee235955bade4b4fe664a903378719a to before 145203420c579a703008b4b723b6a080757f4964Affected

References

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