Vulnerability · Published Jun 29, 2026 · Assigned by apache
CVE-2026-55956Apache Tomcat: Security constraints for default servlet ignored method
Medium 6.5
In plain English
A medium-severity security flaw in Apache Tomcat from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.7%top 46.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Improper Authorization vulnerability in Apache Tomcat leads to security constraints specified for the default servlet ignoring any method or method omission configured as part of the constraint. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fix the issue.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | tomcat | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat | 1:9.0.120-2.el9_8 | ALSA-2026:68660 |
| AlmaLinux:8 | tomcat-admin-webapps | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-admin-webapps | 1:9.0.120-2.el9_8 | ALSA-2026:68660 |
| AlmaLinux:8 | tomcat-docs-webapp | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-docs-webapp | 1:9.0.120-2.el9_8 | ALSA-2026:68660 |
| AlmaLinux:8 | tomcat-el-3.0-api | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-el-3.0-api | 1:9.0.120-2.el9_8 | ALSA-2026:68660 |
| AlmaLinux:8 | tomcat-jsp-2.3-api | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-jsp-2.3-api | 1:9.0.120-2.el9_8 | ALSA-2026:68660 |
| AlmaLinux:8 | tomcat-lib | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-lib | 1:9.0.120-2.el9_8 | ALSA-2026:68660 |
| AlmaLinux:8 | tomcat-servlet-4.0-api | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-servlet-4.0-api | 1:9.0.120-2.el9_8 | ALSA-2026:68660 |
| AlmaLinux:8 | tomcat-webapps | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-webapps | 1:9.0.120-2.el9_8 | ALSA-2026:68660 |
| AlmaLinux:10 | tomcat9 | 1:9.0.120-1.el10_2.alma.1 | ALSA-2026:68651 |
| AlmaLinux:10 | tomcat9-admin-webapps | 1:9.0.120-1.el10_2.alma.1 | ALSA-2026:68651 |
| AlmaLinux:10 | tomcat9-docs-webapp | 1:9.0.120-1.el10_2.alma.1 | ALSA-2026:68651 |
| AlmaLinux:10 | tomcat9-el-3.0-api | 1:9.0.120-1.el10_2.alma.1 | ALSA-2026:68651 |
| AlmaLinux:10 | tomcat9-jsp-2.3-api | 1:9.0.120-1.el10_2.alma.1 | ALSA-2026:68651 |
| AlmaLinux:10 | tomcat9-lib | 1:9.0.120-1.el10_2.alma.1 | ALSA-2026:68651 |
| AlmaLinux:10 | tomcat9-servlet-4.0-api | 1:9.0.120-1.el10_2.alma.1 | ALSA-2026:68651 |
| AlmaLinux:10 | tomcat9-webapps | 1:9.0.120-1.el10_2.alma.1 | ALSA-2026:68651 |
| Debian:12 | tomcat10 | no fix listed | DEBIAN-CVE-2026-55956 |
| Debian:13 | tomcat10 | no fix listed | DEBIAN-CVE-2026-55956 |
| Debian:14 | tomcat10 | 10.1.60-1 | DEBIAN-CVE-2026-55956 |
| Debian:13 | tomcat11 | no fix listed | DEBIAN-CVE-2026-55956 |
| Debian:14 | tomcat11 | 11.0.24-1 | DEBIAN-CVE-2026-55956 |
| Debian:12 | tomcat9 | 9.0.70-2 | DEBIAN-CVE-2026-55956 |
| Debian:13 | tomcat9 | 9.0.70-2 | DEBIAN-CVE-2026-55956 |
| Debian:14 | tomcat9 | 9.0.70-2 | DEBIAN-CVE-2026-55956 |
| Maven | org.apache.tomcat.embed:tomcat-embed-core | 9.0.119 | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat.embed:tomcat-embed-core | no fix listed | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat.embed:tomcat-embed-core | no fix listed | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat.embed:tomcat-embed-core | 11.0.23 | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat.embed:tomcat-embed-core | 10.1.56 | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat | 10.1.56 | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat | no fix listed | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat | no fix listed | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat | 11.0.23 | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat | 9.0.119 | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat-catalina | 10.1.56 | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat-catalina | no fix listed | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat-catalina | no fix listed | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat-catalina | 11.0.23 | GHSA-5v3h-fjv2-54fg |
| Maven | org.apache.tomcat:tomcat-catalina | 9.0.119 | GHSA-5v3h-fjv2-54fg |
| Ubuntu:24.04:LTS | tomcat10 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:25.10 | tomcat10 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:26.04:LTS | tomcat10 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:26.10 | tomcat10 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:25.10 | tomcat11 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:26.04:LTS | tomcat11 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:26.10 | tomcat11 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:24.04:LTS | tomcat9 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:25.10 | tomcat9 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:26.04:LTS | tomcat9 | no fix listed | UBUNTU-CVE-2026-55956 |
| Ubuntu:26.10 | tomcat9 | no fix listed | UBUNTU-CVE-2026-55956 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache Tomcat | 11.0.0-M1 – through 11.0.2210.1.0-M1 – through 10.1.559.0.0.M1 – through 9.0.1188.5.0 – through 8.5.1007.0.0 – through 7.0.109 |
Weakness: CWE-285 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N