Description
If a web application sends a WebSocket message concurrently with the WebSocket connection closing when running on Apache Tomcat 8.5.0 to 8.5.75 or Apache Tomcat 9.0.0.M1 to 9.0.20, it is possible that the application will continue to use the socket after it has been closed. The error handling triggered in this case could cause the a pooled object to be placed in the pool twice. This could result in subsequent connections using the same object concurrently which could result in data being returned to the wrong use and/or other errors.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Apache Software Foundation | Apache Tomcat | Apache Tomcat 9 9.0.0.M1 to 9.0.20, Apache Tomcat 8.5 8.5.0 to 8.5.75 | — |
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 | tomcat9 | 9.0.22-1 | — |
| Debian 13 | tomcat9 | 9.0.22-1 | — |
| Debian 12 | tomcat9 | 9.0.22-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | tomcat8 +1 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | apache-commons-collections | 3.2.2-10.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | apache-commons-lang | 2.6-21.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | apache-commons-net | 3.6-3.module+el8.3.0+6805+72837426 | RHSA-2020:4847 |
| RHEL 8 | bea-stax +1 | 1.2.0-16.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | glassfish-fastinfoset | 1.2.13-9.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | glassfish-jaxb +3 | 2.2.11-11.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | glassfish-jaxb-api | 2.2.12-8.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | jackson-core +2 | 2.10.0-1.module+el8.2.0+5059+3eb3af25 | RHSA-2020:4847 |
| RHEL 8 | jackson-jaxrs-providers +1 | 2.9.9-1.module+el8.1.0+3832+9784644d | RHSA-2020:4847 |
| RHEL 8 | jackson-module-jaxb-annotations | 2.7.6-4.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | jakarta-commons-httpclient | 1:3.1-28.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | javassist +1 | 3.18.1-8.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | jss +1 | 4.7.3-1.module+el8.3.0+8058+d5cd4219 | RHSA-2020:4847 |
| RHEL 8 | ldapjdk +1 | 4.22.0-1.module+el8.3.0+6784+6e1e4c62 | RHSA-2020:4847 |
| RHEL 8 | pki-ca +8 | 10.9.4-1.module+el8.3.0+8058+d5cd4219 | RHSA-2020:4847 |
| RHEL 8 | pki-servlet-engine +1 | 1:9.0.30-1.module+el8.3.0+6730+8f9c6254 | RHSA-2020:4847 |
| RHEL 8 | python-nss +2 | 1.0.1-10.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | relaxngDatatype | 2011.1-7.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | resteasy | 3.0.26-3.module+el8.2.0+5723+4574fbff | RHSA-2020:4847 |
| RHEL 8 | slf4j +1 | 1.7.25-4.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | stax-ex | 1.7.7-8.module+el8.2.0+5723+4574fbff | RHSA-2020:4847 |
| RHEL 8 | tomcatjss | 7.5.0-1.module+el8.3.0+7355+c59bcbd9 | RHSA-2020:4847 |
| RHEL 8 | velocity | 1.7-24.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | xalan-j2 | 2.7.1-38.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | xerces-j2 | 2.11.0-34.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | xml-commons-apis | 1.4.01-25.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | xml-commons-resolver | 1.2-26.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
| RHEL 8 | xmlstreambuffer | 1.5.4-8.module+el8.2.0+5723+4574fbff | RHSA-2020:4847 |
| RHEL 8 | xsom | 0-19.20110809svn.module+el8.1.0+3366+6dfb954c | RHSA-2020:4847 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | apache-commons-collections | 3.2.2-10.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | apache-commons-lang | 2.6-21.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | apache-commons-net | 3.6-3.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | bea-stax | 1.2.0-16.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | glassfish-fastinfoset | 1.2.13-9.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | glassfish-jaxb | 2.2.11-11.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | glassfish-jaxb-api | 2.2.12-8.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | jackson-core +2 | 2.10.0-1.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | jackson-jaxrs-providers | 2.9.9-1.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | jackson-module-jaxb-annotations | 2.7.6-4.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | jakarta-commons-httpclient | 1:3.1-28.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | javassist | 3.18.1-8.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | ldapjdk | 4.22.0-1.module+el8.4.0+418+b7ae1d4a | RLSA-2020:4847 |
| Rocky Linux 8 | pki-servlet-engine | 1:9.0.30-1.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | python-nss | 1.0.1-10.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | relaxngDatatype | 2011.1-7.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | resteasy | 3.0.26-3.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | slf4j | 1.7.25-4.module+el8.3.0+74+855e3f5d | RLSA-2020:4847 |
| Rocky Linux 8 | stax-ex | 1.7.7-8.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | velocity | 1.7-24.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | xalan-j2 | 2.7.1-38.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | xerces-j2 | 2.11.0-34.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | xml-commons-apis | 1.4.01-25.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | xml-commons-resolver | 1.2-26.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | xmlstreambuffer | 1.5.4-8.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
| Rocky Linux 8 | xsom | 0-19.20110809svn.module+el8.3.0+53+ea062990 | RLSA-2020:4847 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.apache.tomcat:tomcat | >= 8.5.0, < 8.5.75 | 8.5.75 | GHSA-h3ch-5pp2-vh6w |
| Maven | org.apache.tomcat:tomcat | >= 9.0.0M1, < 9.0.20 | 9.0.20 | GHSA-h3ch-5pp2-vh6w |
Advisories 5
- RHSA-2020:4847 Red Hat Security Advisory: pki-core:10.6 and pki-deps:10.6 security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Oct 8, 2026
- RLSA-2020:4847 Moderate: pki-core:10.6 and pki-deps:10.6 security, bug fix, and enhancement update Rocky Linux Security Advisories · Feb 5, 2026
- WID-SEC-2022-0899 Apache Tomcat: Schwachstelle ermöglicht Offenlegung von Informationen BSI CERT-Bund (WID) · Jan 25, 2026
- WID-SEC-2022-1335 Xerox FreeFlow Print Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 6, 2025
- NCSC-2025-0123 Kwetsbaarheden verholpen in Oracle Database Producten NCSC-NL (Netherlands) · Apr 16, 2025