{"id":"CVE-2026-105242","state":"PUBLISHED","title":"Apache log4net: Request validation failure drops the event in the aspnet-request converter","description":"Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net.\n\nReading 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.\n\nThis issue affects Apache log4net: from 1.2.11 before 3.5.0.\n\nUsers are recommended to upgrade to version 3.5.0, which fixes the issue.","publishedAt":"2026-10-06T19:50:19.075Z","updatedAt":"2026-10-07T14:49:06.441Z","severity":{"score":5.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","source":"apache"},"assigner":"apache","products":["Apache Software Foundation Apache log4net"],"affected":[{"vendor":"Apache Software Foundation","product":"Apache log4net","packageName":"log4net","packageURL":"pkg:nuget/log4net","defaultStatus":"unaffected","versions":[{"version":"1.2.11","status":"affected","lessThan":"3.5.0","versionType":"semver"}],"collectionURL":"https://nuget.org/packages"},{"vendor":"Apache Software Foundation","product":"Apache log4net","packageName":"log4net","packageURL":"pkg:nuget/log4net","defaultStatus":"unaffected","versions":[{"version":"243f1e9f3ee235955bade4b4fe664a903378719a","status":"affected","lessThan":"145203420c579a703008b4b723b6a080757f4964","versionType":"git"}],"repo":"https://gitbox.apache.org/repos/asf/logging-log4net.git","collectionURL":"https://nuget.org/packages"}],"references":["https://github.com/apache/logging-log4net/pull/316","https://github.com/apache/logging-log4net/commit/145203420c579a703008b4b723b6a080757f4964","https://lists.apache.org/thread.html/zg6dbqm4ztm7j3c21nfsqj0yxm5yrpdx","http://www.openwall.com/lists/oss-security/2026/10/07/16"],"weaknesses":["CWE-755"],"ingestedAt":"2026-10-29T20:10:23.711Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/105xxx/CVE-2026-105242.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-105242","state":"PUBLISHED","datePublished":"2026-10-06T19:50:19.075Z","dateUpdated":"2026-10-07T14:49:06.441Z","assignerShortName":"apache","assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateReserved":"2026-10-04T16:21:12.546Z"},"containers":{"cna":{"title":"Apache log4net: Request validation failure drops the event in the aspnet-request converter","descriptions":[{"lang":"en","value":"Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net.\n\nReading 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. 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