CVE-2020-9488

low

Description

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

References

https://www.oracle.com/security-alerts/cpuoct2021.html

https://www.oracle.com/security-alerts/cpuoct2020.html

https://www.oracle.com/security-alerts/cpujul2020.html

https://www.oracle.com/security-alerts/cpujan2021.html

https://www.oracle.com/security-alerts/cpuapr2022.html

https://www.oracle.com/security-alerts/cpuApr2021.html

https://www.debian.org/security/2021/dsa-5020

https://security.netapp.com/advisory/ntap-20200504-0003/

https://lists.debian.org/debian-lts-announce/2021/12/msg00017.html

https://www.tenable.com/blog/oracle-april-2021-critical-patch-update-addresses-257-cves-including-zerologon-cve-2020-1472

https://www.tenable.com/blog/oracle-january-2021-critical-patch-update-five-critical-weblogic-flaws-cve-2021-2109

https://github.com/hkelley/PsNvdCvss

https://github.com/ManuelBravoR/NVD-CVE-Scanner-TelegramNotifier

https://github.com/ahmadk18361/Vulnerability-scanner-pipeline

https://github.com/arsalanraja987/java-log4j-cve-2020-9488

https://github.com/HynekPetrak/log4shell-finder

https://github.com/advisories/GHSA-vwqq-5vrc-xw9h

https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E

https://lists.apache.org/thread.html/rf1c2a81a08034c688b8f15cf58a4cfab322d00002ca46d20133bee20%40%3Cdev.kafka.apache.org%3E

https://lists.apache.org/thread.html/rec34b1cccf907898e7cb36051ffac3ccf1ea89d0b261a2a3b3fb267f%40%3Ccommits.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/re024d86dffa72ad800f2848d0c77ed93f0b78ee808350b477a6ed987%40%3Cgitbox.hive.apache.org%3E

https://lists.apache.org/thread.html/rd8e87c4d69df335d0ba7d815b63be8bd8a6352f429765c52eb07ddac%40%3Cissues.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/rd5d58088812cf8e677d99b07f73c654014c524c94e7fedbdee047604%40%3Ctorque-dev.db.apache.org%3E

https://lists.apache.org/thread.html/rd55f65c6822ff235eda435d31488cfbb9aa7055cdf47481ebee777cc%40%3Cissues.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/rd0e44e8ef71eeaaa3cf3d1b8b41eb25894372e2995ec908ce7624d26%40%3Ccommits.pulsar.apache.org%3E

https://lists.apache.org/thread.html/rc6b81c013618d1de1b5d6b8c1088aaf87b4bacc10c2371f15a566701%40%3Cnotifications.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/rc2dbc4633a6eea1fcbce6831876cfa17b73759a98c65326d1896cb1a%40%3Ctorque-dev.db.apache.org%3E

https://lists.apache.org/thread.html/rbc7642b9800249553f13457e46b813bea1aec99d2bc9106510e00ff3%40%3Ctorque-dev.db.apache.org%3E

https://lists.apache.org/thread.html/rbc45eb0f53fd6242af3e666c2189464f848a851d408289840cecc6e3%40%3Ccommits.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/ra632b329b2ae2324fabbad5da204c4ec2e171ff60348ec4ba698fd40%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/ra051e07a0eea4943fa104247e69596f094951f51512d42c924e86c75%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r9a79175c393d14d760a0ae3731b4a873230a16ef321aa9ca48a810cd%40%3Cissues.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/r9776e71e3c67c5d13a91c1eba0dc025b48b802eb7561cc6956d6961c%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r8e96c340004b7898cad3204ea51280ef6e4b553a684e1452bf1b18b1%40%3Cjira.kafka.apache.org%3E

https://lists.apache.org/thread.html/r8c001b9a95c0bbec06f4457721edd94935a55932e64b82cc5582b846%40%3Cissues.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/r7e739f2961753af95e2a3a637828fb88bfca68e5d6b0221d483a9ee5%40%3Cnotifications.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/r7e5c10534ed06bf805473ac85e8412fe3908a8fa4cabf5027bf11220%40%3Cdev.kafka.apache.org%3E

https://lists.apache.org/thread.html/r7641ee788e1eb1be4bb206a7d15f8a64ec6ef23e5ec6132d5a567695%40%3Cnotifications.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/r65578f3761a89bc164e8964acd5d913b9f8fd997967b195a89a97ca3%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r5a68258e5ab12532dc179edae3d6e87037fa3b50ab9d63a90c432507%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r4ed1f49616a8603832d378cb9d13e7a8b9b27972bb46d946ccd8491f%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r4db540cafc5d7232c62e076051ef661d37d345015b2e59b3f81a932f%40%3Cdev.hive.apache.org%3E

https://lists.apache.org/thread.html/r4d5dc9f3520071338d9ebc26f9f158a43ae28a91923d176b550a807b%40%3Cdev.hive.apache.org%3E

https://lists.apache.org/thread.html/r48efc7cb5aeb4e1f67aaa06fb4b5479a5635d12f07d0b93fc2d08809%40%3Ccommits.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/r48bcd06049c1779ef709564544c3d8a32ae6ee5c3b7281a606ac4463%40%3Cjira.kafka.apache.org%3E

https://lists.apache.org/thread.html/r45916179811a32cbaa500f972de9098e6ee80ee81c7f134fce83e03a%40%3Cissues.flink.apache.org%3E

https://lists.apache.org/thread.html/r4285398e5585a0456d3d9db021a4fce6e6fcf3ec027dfa13a450ec98%40%3Cissues.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/r3d1d00441c55144a4013adda74b051ae7864128ebcfb6ee9721a2eb3%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r393943de452406f0f6f4b3def9f8d3c071f96323c1f6ed1a098f7fe4%40%3Ctorque-dev.db.apache.org%3E

https://lists.apache.org/thread.html/r33864a0fc171c1c4bf680645ebb6d4f8057899ab294a43e1e4fe9d04%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r2f209d271349bafd91537a558a279c08ebcff8fa3e547357d58833e6%40%3Cdev.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/r2721aba31a8562639c4b937150897e24f78f747cdbda8641c0f659fe%40%3Cusers.kafka.apache.org%3E

https://lists.apache.org/thread.html/r22a56beb76dd8cf18e24fda9072f1e05990f49d6439662d3782a392f%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r1fc73f0e16ec2fa249d3ad39a5194afb9cc5afb4c023dc0bab5a5881%40%3Cissues.hive.apache.org%3E

https://lists.apache.org/thread.html/r0df3d7a5acb98c57e64ab9266aa21eeee1d9b399addb96f9cf1cbe05%40%3Cdev.zookeeper.apache.org%3E

https://lists.apache.org/thread.html/r0a2699f724156a558afd1abb6c044fb9132caa66dce861b82699722a%40%3Cjira.kafka.apache.org%3E

https://issues.apache.org/jira/browse/LOG4J2-2819

Details

Source: Mitre, NVD

Published: 2020-04-27

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 4.3

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 3.7

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

Severity: Low

EPSS

EPSS: 0.00017