{"schema":"threatline.record/2","record":{"id":"CVE-2026-105241","aliases":[],"summary":"Apache log4net: Unencodable content discards a whole SmtpPickupDirAppender batch","details":"Improper Handling of Unicode Encoding vulnerability in the SmtpPickupDirAppender of Apache log4net.\n\nContent that the mail file writer cannot encode, such as an unpaired UTF-16 surrogate, made the write throw. Every buffered event in the batch was discarded, not only the one carrying the content, and a truncated mail could be left in the pickup directory. A party whose data reaches a log message could suppress the records of other events. Only applications that use SmtpPickupDirAppender are affected.\n\nThis issue affects Apache log4net: from 1.2.9 before 3.5.0.\n\nUsers are recommended to upgrade to version 3.5.0, which fixes the issue.","categories":["Unclassified"],"product":"Apache log4net","vendor":"Apache Software Foundation","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-105241","source_modified_at":"2026-10-07T14:45:58.074Z","fetched_at":"2026-10-23T18:48:36.087640Z","product":"Apache log4net","vendor":"Apache Software Foundation","versions":[{"status":"affected","version":"1.2.9","lessThan":"3.5.0","versionType":"semver"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-105241","source_modified_at":"2026-10-07T14:45:58.074Z","fetched_at":"2026-10-23T18:48:36.087640Z","product":"Apache log4net","vendor":"Apache Software Foundation","versions":[{"status":"affected","version":"02e1e115435888485f2e28b414d267e39e799e07","lessThan":"4d2e10f0908199604b4326f9df6d0b43b871e333","versionType":"git"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-105241","source_modified_at":"2026-10-07T14:45:58.074Z","fetched_at":"2026-10-23T18:48:36.087640Z","package":{"name":"Apache log4net","ecosystem":null},"version":"3.5.0","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-105241","source_modified_at":"2026-10-07T14:45:58.074Z","fetched_at":"2026-10-23T18:48:36.087640Z","package":{"name":"Apache log4net","ecosystem":null},"version":"4d2e10f0908199604b4326f9df6d0b43b871e333","basis":"first unaffected version stated in the CVE record"}],"cvss":5.3,"severity":"Medium","kev":{"listed":false},"epss":{"probability":0.00823,"percentile":0.56947,"score_date":"2026-10-23"},"published_at":"2026-10-06T19:49:03.994Z","modified_at":"2026-10-07T14:45:58.074Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-105241","fetched_at":"2026-10-23T18:48:36.087640Z","source_modified_at":"2026-10-07T14:45:58.074Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-105241","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/apache/logging-log4net/pull/315","tags":["patch"]},{"source":"CVE List","url":"https://github.com/apache/logging-log4net/commit/4d2e10f0908199604b4326f9df6d0b43b871e333","tags":["patch"]},{"source":"CVE List","url":"https://lists.apache.org/thread.html/hg8dgh3oy8bp3dhb8nsygk9kw2o401ws","tags":["vendor-advisory"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"yes","technical_impact":"partial","assessed_at":"2026-10-07T14:44:42.702949Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-07T14:45:58.074Z","content_hash":"f3c2deacf24223b2b64f434c1e64b9a7e6ce45bd759498f658df1f7c4985ab7f"}}