{"id":"CVE-2026-105242","summary":"Apache log4net: Request validation failure drops the event in the aspnet-request converter","details":"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.","modified":"2026-10-09T02:30:52.715498695Z","published":"2026-10-06T19:50:19.075Z","database_specific":{"cna_assigner":"apache","cwe_ids":["CWE-755"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/105xxx/CVE-2026-105242.json"},"references":[{"type":"WEB","url":"http://www.openwall.com/lists/oss-security/2026/10/07/16"},{"type":"WEB","url":"https://nuget.org/packages"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/105xxx/CVE-2026-105242.json"},{"type":"ADVISORY","url":"https://lists.apache.org/thread.html/zg6dbqm4ztm7j3c21nfsqj0yxm5yrpdx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-105242"},{"type":"FIX","url":"https://github.com/apache/logging-log4net/commit/145203420c579a703008b4b723b6a080757f4964"},{"type":"FIX","url":"https://github.com/apache/logging-log4net/pull/316"},{"type":"PACKAGE","url":"https://gitbox.apache.org/repos/asf/logging-log4net.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://gitbox.apache.org/repos/asf/logging-log4net.git","events":[{"introduced":"243f1e9f3ee235955bade4b4fe664a903378719a"},{"fixed":"145203420c579a703008b4b723b6a080757f4964"}]},{"type":"GIT","repo":"https://github.com/apache/logging-log4net","events":[{"introduced":"957ba369261d963e228916ea1954c5f2f532d9b3"},{"fixed":"f7794ae187ab2e228e1754cb478568dd305d1b32"},{"fixed":"145203420c579a703008b4b723b6a080757f4964"}],"database_specific":{"source":["DESCRIPTION","REFERENCES"],"extracted_events":[{"introduced":"1.2.11"},{"fixed":"3.5.0"}]}}],"versions":["rc/3.4.1-preview.1","rel/3.4.0","rc/3.4.0-rc1","rc/3.4.0-preview.1","rel/3.3.2","rc/3.3.2-rc1","rel/3.3.1","rc/3.3.1-rc1","rel/3.3.0","rc/3.3.0-rc1","rc/3.2.0-rc1","rc/temp","rel/3.2.0","rc/3.2.0-preview.1","rel/3.1.0","rc/3.1.0-rc1","rel/3.0.4","rc/3.0.4-rc1","rc/3.0.4-preview.1","rel/3.0.3","rc/3.0.3-rc1","rc/3.0.3-preview.1","rel/3.0.2","rc/3.0.2-rc1","rel/3.0.1","rc/3.0.1-rc1","rc/3.0.1-preview.2","rc/3.0.1-preview.1","rel/2.x","rel/2.0.17","rel/2.0.16","rel/2.0.15","rel/2.0.14","rel/2.0.13","rel/2.0.12","rel/2.0.11","rel/2.0.10"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-105242.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"}]}