{"id":"CVE-2026-105244","state":"PUBLISHED","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.","publishedAt":"2026-10-06T19:52:31.116Z","updatedAt":"2026-10-07T14:50:49.648Z","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":"1.2.12","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":"56a2e146e21ff4737e1ff3ec308810e667873947","status":"affected","lessThan":"77717061b20d4346b6c0ce6b54643d85fb348bc7","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/315","https://github.com/apache/logging-log4net/commit/77717061b20d4346b6c0ce6b54643d85fb348bc7","https://lists.apache.org/thread.html/q7649hhdodthoqw8jsjgtnb4m8qfy6d6","http://www.openwall.com/lists/oss-security/2026/10/07/19"],"weaknesses":["CWE-116"],"ingestedAt":"2026-10-29T20:10:23.711Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/105xxx/CVE-2026-105244.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-105244","state":"PUBLISHED","datePublished":"2026-10-06T19:52:31.116Z","dateUpdated":"2026-10-07T14:50:49.648Z","assignerShortName":"apache","assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","dateReserved":"2026-10-04T16:22:18.416Z"},"containers":{"cna":{"title":"Apache log4net: RemoteSyslogAppender silently deletes non-ASCII content","descriptions":[{"lang":"en","value":"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. 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