Vulnerability · Published Feb 17, 2026 · Assigned by apache
CVE-2026-24733Apache Tomcat: Security constraint bypass with HTTP/0.9
Medium 6.5
In plain English
A medium-severity improper input validation 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 0.6% (higher than 46% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
Improper Input Validation vulnerability in Apache Tomcat. Tomcat did not limit HTTP/0.9 requests to the GET method. If a security constraint was configured to allow HEAD requests to a URI but deny GET requests, the user could bypass that constraint on GET requests by sending a (specification invalid) HEAD request using HTTP/0.9. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.14, from 10.1.0-M1 through 10.1.49, from 9.0.0.M1 through 9.0.112. Older, EOL versions are also affected. Users are recommended to upgrade to version 11.0.15 or later, 10.1.50 or later or 9.0.113 or later, which fixes 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 | 1:9.0.117-1.el9_8 | ALSA-2026:26323 |
| AlmaLinux:8 | tomcat-admin-webapps | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-admin-webapps | 1:9.0.117-1.el9_8 | ALSA-2026:26323 |
| AlmaLinux:8 | tomcat-docs-webapp | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-docs-webapp | 1:9.0.117-1.el9_8 | ALSA-2026:26323 |
| AlmaLinux:8 | tomcat-el-3.0-api | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-el-3.0-api | 1:9.0.117-1.el9_8 | ALSA-2026:26323 |
| AlmaLinux:8 | tomcat-jsp-2.3-api | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-jsp-2.3-api | 1:9.0.117-1.el9_8 | ALSA-2026:26323 |
| AlmaLinux:8 | tomcat-lib | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-lib | 1:9.0.117-1.el9_8 | ALSA-2026:26323 |
| AlmaLinux:8 | tomcat-servlet-4.0-api | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-servlet-4.0-api | 1:9.0.117-1.el9_8 | ALSA-2026:26323 |
| AlmaLinux:8 | tomcat-webapps | 1:9.0.120-1.el8_10 | ALSA-2026:68677 |
| AlmaLinux:9 | tomcat-webapps | 1:9.0.117-1.el9_8 | ALSA-2026:26323 |
| AlmaLinux:10 | tomcat9 | 1:9.0.117-1.el10_2.alma.1 | ALSA-2026:25341 |
| AlmaLinux:10 | tomcat9 | 1:9.0.117-2.el10_2.alma.1 | ALSA-2026:36790 |
| AlmaLinux:10 | tomcat9-admin-webapps | 1:9.0.117-1.el10_2.alma.1 | ALSA-2026:25341 |
| AlmaLinux:10 | tomcat9-admin-webapps | 1:9.0.117-2.el10_2.alma.1 | ALSA-2026:36790 |
| AlmaLinux:10 | tomcat9-docs-webapp | 1:9.0.117-1.el10_2.alma.1 | ALSA-2026:25341 |
| AlmaLinux:10 | tomcat9-docs-webapp | 1:9.0.117-2.el10_2.alma.1 | ALSA-2026:36790 |
| AlmaLinux:10 | tomcat9-el-3.0-api | 1:9.0.117-1.el10_2.alma.1 | ALSA-2026:25341 |
| AlmaLinux:10 | tomcat9-el-3.0-api | 1:9.0.117-2.el10_2.alma.1 | ALSA-2026:36790 |
| AlmaLinux:10 | tomcat9-jsp-2.3-api | 1:9.0.117-2.el10_2.alma.1 | ALSA-2026:36790 |
| AlmaLinux:10 | tomcat9-jsp-2.3-api | 1:9.0.117-1.el10_2.alma.1 | ALSA-2026:25341 |
| AlmaLinux:10 | tomcat9-lib | 1:9.0.117-2.el10_2.alma.1 | ALSA-2026:36790 |
| AlmaLinux:10 | tomcat9-lib | 1:9.0.117-1.el10_2.alma.1 | ALSA-2026:25341 |
| AlmaLinux:10 | tomcat9-servlet-4.0-api | 1:9.0.117-2.el10_2.alma.1 | ALSA-2026:36790 |
| AlmaLinux:10 | tomcat9-servlet-4.0-api | 1:9.0.117-1.el10_2.alma.1 | ALSA-2026:25341 |
| AlmaLinux:10 | tomcat9-webapps | 1:9.0.117-2.el10_2.alma.1 | ALSA-2026:36790 |
| AlmaLinux:10 | tomcat9-webapps | 1:9.0.117-1.el10_2.alma.1 | ALSA-2026:25341 |
| Debian:12 | tomcat10 | 10.1.52-1~deb12u1 | DEBIAN-CVE-2026-24733 |
| Debian:12 | tomcat10 | 10.1.52-1~deb12u1 | DSA-6120-1 |
| Debian:13 | tomcat10 | 10.1.52-1~deb13u1 | DSA-6120-1 |
| Debian:13 | tomcat10 | 10.1.52-1~deb13u1 | DEBIAN-CVE-2026-24733 |
| Debian:14 | tomcat10 | 10.1.52-1 | DEBIAN-CVE-2026-24733 |
| Debian:13 | tomcat11 | 11.0.15-1~deb13u1 | DEBIAN-CVE-2026-24733 |
| Debian:13 | tomcat11 | 11.0.15-1~deb13u1 | DSA-6121-1 |
| Debian:14 | tomcat11 | 11.0.15-1 | DEBIAN-CVE-2026-24733 |
| Debian:12 | tomcat9 | 9.0.70-2 | DEBIAN-CVE-2026-24733 |
| Debian:13 | tomcat9 | 9.0.70-2 | DEBIAN-CVE-2026-24733 |
| Debian:14 | tomcat9 | 9.0.70-2 | DEBIAN-CVE-2026-24733 |
| Maven | org.apache.tomcat:tomcat-coyote | 10.1.50 | GHSA-qq5r-98hh-rxc9 |
| Maven | org.apache.tomcat:tomcat-coyote | 11.0.15 | GHSA-qq5r-98hh-rxc9 |
| Maven | org.apache.tomcat:tomcat-coyote | 9.0.113 | GHSA-qq5r-98hh-rxc9 |
| Rocky Linux:10 | tomcat9 | 1:9.0.117-1.el10_2 | RLSA-2026:25341 |
| Ubuntu:24.04:LTS | tomcat10 | no fix listed | UBUNTU-CVE-2026-24733 |
| Ubuntu:25.10 | tomcat10 | no fix listed | UBUNTU-CVE-2026-24733 |
| Ubuntu:26.04:LTS | tomcat10 | no fix listed | UBUNTU-CVE-2026-24733 |
| Ubuntu:25.10 | tomcat11 | no fix listed | UBUNTU-CVE-2026-24733 |
| Ubuntu:24.04:LTS | tomcat9 | no fix listed | UBUNTU-CVE-2026-24733 |
| Ubuntu:25.10 | tomcat9 | no fix listed | UBUNTU-CVE-2026-24733 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache Tomcat | 11.0.0-M1 – through 11.0.1410.1.0-M1 – through 10.1.499.0.0.M1 – through 9.0.1120 – through 8.5.100 |
Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
References
- https://lists.apache.org/thread/6xk3t65qpn1myp618krtfotbjn1qt90f vendor-advisory