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
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Apache | Apache Log4j | log4j-core 2.13.0, log4j-core – < 2.12.3 | 2.12.3 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | apache-log4j2 | 2.13.3-1 | — |
| Debian 13 | apache-log4j2 | 2.13.3-1 | — |
| Debian 12 | apache-log4j2 | 2.13.3-1 | — |
| Debian 9 | apache-log4j2 | 2.12.3-0+deb9u1 | DLA-2852-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | apache-log4j2 | 2.16.0-0.20.04.1 | — |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 16.04 LTS | apache-log4j2 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat A Mq Clients 2 | nodejs-rhea | 1.0.24-1.el8 | RHSA-2020:3817 |
| Red Hat A Mq Clients 2 | python3-qpid-proton | 0.32.0-2.el8 | RHSA-2020:3817 |
| Red Hat A Mq Clients 2 | qpid-cpp +3 | 1.36.0-31.el6_10amq | RHSA-2020:3817 |
| Red Hat A Mq Clients 2 | qpid-proton +9 | 0.32.0-1.el6_10 | RHSA-2020:3817 |
| Red Hat A Mq Clients 2 | rubygem-qpid_proton | 0.32.0-2.el7 | RHSA-2020:3817 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
GitHub 1 repository
-
arsalanraja987/java-log4j-cve-2020-9488 ★ 0 · Jul 7, 2025
Demo of CVE-2020-9488: Unsafe logging with Log4j and remediation
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.apache.logging.log4j:log4j | >= 2.13.0, < 2.13.2 | 2.13.2 | GHSA-vwqq-5vrc-xw9h |
| Maven | org.apache.logging.log4j:log4j | >= 2.4.0, < 2.12.3 | 2.12.3 | GHSA-vwqq-5vrc-xw9h |
| Maven | org.apache.logging.log4j:log4j | < 2.3.2 | 2.3.2 | GHSA-vwqq-5vrc-xw9h |
| Maven | org.apache.logging.log4j:log4j-core | >= 2.13.0, < 2.13.2 | 2.13.2 | GHSA-vwqq-5vrc-xw9h |
| Maven | org.apache.logging.log4j:log4j-core | >= 2.4.0, < 2.12.3 | 2.12.3 | GHSA-vwqq-5vrc-xw9h |
| Maven | org.apache.logging.log4j:log4j-core | < 2.3.2 | 2.3.2 | GHSA-vwqq-5vrc-xw9h |
Advisories 5
- WID-SEC-2024-0794 Dell ECS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 11, 2026
- RHSA-2020:3817 Red Hat Security Advisory: AMQ Clients 2.8.0 Release Red Hat Security Advisories (RHSA) · Aug 5, 2026
- DLA-2852-1 apache-log4j2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- WID-SEC-2024-2181 Oracle Fusion Middleware: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 18, 2024
- WID-SEC-2023-1048 Oracle Construction and Engineering: Mehrere Schwachstellen BSI CERT-Bund (WID) · Feb 4, 2024
References
- [zookeeper-issues] 20200504 [jira] [Created] (ZOOKEEPER-3817) owasp failing due to CVE-2020-9488 mailing-list
- [zookeeper-dev] 20200504 [jira] [Created] (ZOOKEEPER-3817) owasp failing due to CVE-2020-9488 mailing-list
- [zookeeper-notifications] 20200504 Build failed in Jenkins: zookeeper-master-maven-owasp #489 mailing-list
- [zookeeper-issues] 20200504 [jira] [Assigned] (ZOOKEEPER-3817) owasp failing due to CVE-2020-9488 mailing-list
- [zookeeper-issues] 20200504 [jira] [Commented] (ZOOKEEPER-3817) owasp failing due to CVE-2020-9488 mailing-list
- [zookeeper-dev] 20200504 log4j SmtpAppender related CVE mailing-list
- [zookeeper-notifications] 20200504 [GitHub] [zookeeper] symat opened a new pull request #1346: ZOOKEEPER-3817: suppress log4j SmtpAppender related CVE-2020-9488 mailing-list
- [zookeeper-issues] 20200504 [jira] [Updated] (ZOOKEEPER-3817) owasp failing due to CVE-2020-9488 mailing-list
- [zookeeper-commits] 20200504 [zookeeper] branch master updated: ZOOKEEPER-3817: suppress log4j SmtpAppender related CVE-2020-9488 mailing-list
- [zookeeper-commits] 20200504 [zookeeper] branch branch-3.5 updated: ZOOKEEPER-3817: suppress log4j SmtpAppender related CVE-2020-9488 mailing-list
- [zookeeper-commits] 20200504 [zookeeper] branch branch-3.6 updated: ZOOKEEPER-3817: suppress log4j SmtpAppender related CVE-2020-9488 mailing-list
- [zookeeper-issues] 20200504 [jira] [Resolved] (ZOOKEEPER-3817) owasp failing due to CVE-2020-9488 mailing-list
- [zookeeper-notifications] 20200504 [GitHub] [zookeeper] symat commented on pull request #1346: ZOOKEEPER-3817: suppress log4j SmtpAppender related CVE-2020-9488 mailing-list
- [kafka-dev] 20200514 [jira] [Created] (KAFKA-9996) upgrade zookeeper to 3.5.8 to address security vulnerabilities mailing-list
- [kafka-jira] 20200514 [jira] [Created] (KAFKA-9996) upgrade zookeeper to 3.5.8 to address security vulnerabilities mailing-list
- [kafka-dev] 20200514 [jira] [Created] (KAFKA-9997) upgrade log4j lib to address CVE-2020-9488 mailing-list
- [kafka-jira] 20200514 [jira] [Created] (KAFKA-9997) upgrade log4j lib to address CVE-2020-9488 mailing-list
- [kafka-jira] 20200515 [jira] [Commented] (KAFKA-9997) upgrade log4j lib to address CVE-2020-9488 mailing-list
- https://www.oracle.com/security-alerts/cpujul2020.html
- https://issues.apache.org/jira/browse/LOG4J2-2819
- https://security.netapp.com/advisory/ntap-20200504-0003/
- [db-torque-dev] 20200715 Build failed in Jenkins: Torque4-trunk #685 mailing-list
- https://www.oracle.com/security-alerts/cpuoct2020.html
- [hive-issues] 20201207 [jira] [Work started] (HIVE-24500) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-issues] 20201207 [jira] [Assigned] (HIVE-24500) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-issues] 20201207 [jira] [Updated] (HIVE-24500) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-dev] 20201207 [jira] [Created] (HIVE-24500) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-issues] 20201208 [jira] [Work logged] (HIVE-24500) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-issues] 20201208 [jira] [Updated] (HIVE-24500) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [pulsar-commits] 20201215 [GitHub] [pulsar] yanshuchong opened a new issue #8967: CVSS issue list mailing-list
- https://www.oracle.com/security-alerts/cpujan2021.html
- https://lists.apache.org/thread.html/re024d86dffa72ad800f2848d0c77ed93f0b78ee808350b477a6ed987%40%3Cgitbox.hive.apache.org%3E
- https://lists.apache.org/thread.html/rbc7642b9800249553f13457e46b813bea1aec99d2bc9106510e00ff3%40%3Ctorque-dev.db.apache.org%3E
- [hive-issues] 20210125 [jira] [Work logged] (HIVE-24500) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [db-torque-dev] 20210127 Re: Items for our (delayed) quarterly report to the board? mailing-list
- [db-torque-dev] 20210128 Antwort: Re: Items for our (delayed) quarterly report to the board? mailing-list
- [hive-issues] 20210209 [jira] [Resolved] (HIVE-24500) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-dev] 20210216 [jira] [Created] (HIVE-24787) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-issues] 20210216 [jira] [Resolved] (HIVE-24787) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-issues] 20210216 [jira] [Assigned] (HIVE-24787) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [hive-issues] 20210218 [jira] [Updated] (HIVE-24787) Hive - upgrade log4j 2.12.1 to 2.13.2+ due to CVE-2020-9488 mailing-list
- [mina-dev] 20210225 [jira] [Created] (FTPSERVER-500) Security vulnerability in common/lib/log4j-1.2.17.jar mailing-list
- [flink-issues] 20210510 [GitHub] [flink] zentol opened a new pull request #15879: [FLINK-22407][build] Bump log4j to 2.24.1 mailing-list
- https://www.oracle.com/security-alerts/cpuApr2021.html
- [kafka-users] 20210617 vulnerabilities mailing-list
- https://www.oracle.com/security-alerts/cpuoct2021.html
- DSA-5020 vendor-advisory
- [debian-lts-announce] 20211226 [SECURITY] [DLA 2852-1] apache-log4j2 security update mailing-list
- https://www.oracle.com/security-alerts/cpuapr2022.html