{"id":"CVE-2026-105244","revision":"d9acc51eba4441e9818cd552b7d3a780","records":[{"revision":"d9acc51eba4441e9818cd552b7d3a780","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-105244","aliases":[],"title":"Apache log4net: RemoteSyslogAppender silently deletes non-ASCII content","description":"Improper Encoding or Escaping of Output vulnerability in the RemoteSyslogAppender of Apache log4net.\n\nEvery character outside visible ASCII and space was removed from the record instead of being escaped, so non-ASCII text and control characters such as tabs disappeared without notice. A party whose data reaches a log message could make a distinct value look identical in the record, for example a user name holding a zero-width space logged as admin. Only applications that use RemoteSyslogAppender are affected.\n\nThis issue affects Apache log4net: from 1.2.12 before 3.5.0.\n\nUsers are recommended to upgrade to version 3.5.0, which fixes the issue.","state":0,"publishedAt":"2026-10-06T19:52:31.116+00:00","modifiedAt":"2026-10-07T14:50:49.648+00:00","affected":[{"ecosystem":"NuGet","name":"log4net","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Apache Software Foundation\",\n                    \"product\": \"Apache log4net\",\n                    \"packageURL\": \"pkg:nuget/log4net\",\n                    \"versions\": [\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"1.2.12\",\n                            \"lessThan\": \"3.5.0\",\n                            \"versionType\": \"semver\"\n                        }\n                    ],\n                    \"defaultStatus\": \"unaffected\",\n                    \"collectionURL\": \"https://nuget.org/packages\",\n                    \"packageName\": \"log4net\"\n                }"},{"ecosystem":"NuGet","name":"log4net","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Apache Software Foundation\",\n                    \"product\": \"Apache log4net\",\n                    \"packageURL\": \"pkg:nuget/log4net\",\n                    \"repo\": \"https://gitbox.apache.org/repos/asf/logging-log4net.git\",\n                    \"versions\": [\n                        {\n                            \"status\": \"affected\",\n                            \"version\": \"56a2e146e21ff4737e1ff3ec308810e667873947\",\n                            \"lessThan\": \"77717061b20d4346b6c0ce6b54643d85fb348bc7\",\n                            \"versionType\": \"git\"\n                        }\n                    ],\n                    \"defaultStatus\": \"unaffected\",\n                    \"collectionURL\": \"https://nuget.org/packages\",\n                    \"packageName\": \"log4net\"\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","score":5.3,"severity":"MEDIUM"}],"references":["https://github.com/apache/logging-log4net/pull/315","https://github.com/apache/logging-log4net/commit/77717061b20d4346b6c0ce6b54643d85fb348bc7","https://lists.apache.org/thread.html/q7649hhdodthoqw8jsjgtnb4m8qfy6d6"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-105244","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-105244","identifiers":["CVE-2026-105244"]},"retained":false,"historicalAffected":[]}],"coverage":[]}