{"id":"CVE-2020-9488","published":"2020-04-27T15:36:10Z","modified":"2026-05-29T16:07:52Z","title":"Improper validation of certificate with host mismatch in Apache Log4j SMTP appender","vendor":"Apache","product":"Apache Log4j","tier":"tail","description":{"text":"Improper validation of certificate with host mismatch in Apache Log4j SMTP appender. This could allow an SMTPS connection to be intercepted by a man-in-the-middle attack which could leak any log messages sent through that appender. Fixed in Apache Log4j 2.12.3 and 2.13.1","provenance":"source","from":"CVE.org"},"cvss":{"score":3.7,"severity":"LOW","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","provenance":"source","from":"CISA ADP Vulnrichment"},"epss":{"score":0.08216,"percentile":0.94863,"provenance":"source"},"cwes":[{"id":"CWE-295","name":"Improper Certificate Validation"}],"references":[{"url":"https://lists.apache.org/thread.html/r8c001b9a95c0bbec06f4457721edd94935a55932e64b82cc5582b846%40%3Cissues.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r2f209d271349bafd91537a558a279c08ebcff8fa3e547357d58833e6%40%3Cdev.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r7641ee788e1eb1be4bb206a7d15f8a64ec6ef23e5ec6132d5a567695%40%3Cnotifications.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/rd8e87c4d69df335d0ba7d815b63be8bd8a6352f429765c52eb07ddac%40%3Cissues.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r4285398e5585a0456d3d9db021a4fce6e6fcf3ec027dfa13a450ec98%40%3Cissues.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r0df3d7a5acb98c57e64ab9266aa21eeee1d9b399addb96f9cf1cbe05%40%3Cdev.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r7e739f2961753af95e2a3a637828fb88bfca68e5d6b0221d483a9ee5%40%3Cnotifications.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r9a79175c393d14d760a0ae3731b4a873230a16ef321aa9ca48a810cd%40%3Cissues.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/rbc45eb0f53fd6242af3e666c2189464f848a851d408289840cecc6e3%40%3Ccommits.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/rec34b1cccf907898e7cb36051ffac3ccf1ea89d0b261a2a3b3fb267f%40%3Ccommits.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r48efc7cb5aeb4e1f67aaa06fb4b5479a5635d12f07d0b93fc2d08809%40%3Ccommits.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/rd55f65c6822ff235eda435d31488cfbb9aa7055cdf47481ebee777cc%40%3Cissues.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/rc6b81c013618d1de1b5d6b8c1088aaf87b4bacc10c2371f15a566701%40%3Cnotifications.zookeeper.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r7e5c10534ed06bf805473ac85e8412fe3908a8fa4cabf5027bf11220%40%3Cdev.kafka.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r8e96c340004b7898cad3204ea51280ef6e4b553a684e1452bf1b18b1%40%3Cjira.kafka.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/rf1c2a81a08034c688b8f15cf58a4cfab322d00002ca46d20133bee20%40%3Cdev.kafka.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r0a2699f724156a558afd1abb6c044fb9132caa66dce861b82699722a%40%3Cjira.kafka.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r48bcd06049c1779ef709564544c3d8a32ae6ee5c3b7281a606ac4463%40%3Cjira.kafka.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://www.oracle.com/security-alerts/cpujul2020.html","tags":["x_refsource_MISC"]},{"url":"https://issues.apache.org/jira/browse/LOG4J2-2819","tags":["x_refsource_CONFIRM"]},{"url":"https://security.netapp.com/advisory/ntap-20200504-0003/","tags":["x_refsource_CONFIRM"]},{"url":"https://lists.apache.org/thread.html/r393943de452406f0f6f4b3def9f8d3c071f96323c1f6ed1a098f7fe4%40%3Ctorque-dev.db.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://www.oracle.com/security-alerts/cpuoct2020.html","tags":["x_refsource_MISC"]},{"url":"https://lists.apache.org/thread.html/r1fc73f0e16ec2fa249d3ad39a5194afb9cc5afb4c023dc0bab5a5881%40%3Cissues.hive.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/ra632b329b2ae2324fabbad5da204c4ec2e171ff60348ec4ba698fd40%40%3Cissues.hive.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r4ed1f49616a8603832d378cb9d13e7a8b9b27972bb46d946ccd8491f%40%3Cissues.hive.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r4db540cafc5d7232c62e076051ef661d37d345015b2e59b3f81a932f%40%3Cdev.hive.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r9776e71e3c67c5d13a91c1eba0dc025b48b802eb7561cc6956d6961c%40%3Cissues.hive.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.apache.org/thread.html/r65578f3761a89bc164e8964acd5d913b9f8fd997967b195a89a97ca3%40%3Cissues.hive.apache.org%3E","tags":["mailing-list","x_refsource_MLIST"]},{"url":"https://lists.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<2.12.3","<2.3.2"],"patched":["2.13.2","2.12.3","2.3.2"],"from":["GHSA-vwqq-5vrc-xw9h"],"provenance":"source"},{"ecosystem":"Maven","package":"org.apache.logging.log4j:log4j-core","vulnerableRanges":[">=2.13.0, <2.13.2",">=2.4.0, <2.12.3","<2.3.2"],"patched":["2.13.2","2.12.3","2.3.2"],"from":["GHSA-vwqq-5vrc-xw9h"],"provenance":"source"}],"euvd":{"id":"EUVD-2020-0518","exploited":false,"provenance":"source"},"lineage":{"packageHistory":[{"cve":"CVE-2023-26464","published":"2023-03-10","fixed":"2.0","kev":false},{"cve":"CVE-2017-5645","published":"2017-04-17","fixed":"2.8.2","kev":false},{"cve":"CVE-2020-9488","published":"2020-04-27","fixed":"2.13.2","kev":false},{"cve":"CVE-2021-44228","published":"2021-12-10","fixed":"2.15.0","kev":true,"link":{"from":"CVE-2020-9488","to":"CVE-2021-44228","relation":"successor","confidence":"low","kind":"sequence","evidence":[{"kind":"version-step","provenance":"source","package":"Maven:org.apache.logging.log4j:log4j-core","fromFixed":"2.13.2","toFixed":"2.15.0","daysApart":592}]}},{"cve":"CVE-2021-45046","published":"2021-12-14","fixed":"2.16.0","kev":true},{"cve":"CVE-2021-45105","published":"2021-12-18","fixed":"2.17.0","kev":false}],"package":"Maven:org.apache.logging.log4j:log4j-core"}}