cbcvebase.
CVE-2026-43515
published 2026-05-12

CVE-2026-43515: Improper Authorization vulnerability when multiple method constraints define an HTTP method for the same extension in Apache Tomcat. This issue affects Apache…

PriorityP262critical9.1CVSS 3.1
AVNACLPRNUINSUCHIHAN
EPSS
1.14%
64.4th percentile
Improper Authorization vulnerability when multiple method constraints define an HTTP method for the same extension in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Users are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118 which fix the issue.

Affected

20 ranges
VendorProductVersion rangeFixed in
apachetomcat>= 10.1.0 < 10.1.5510.1.55
apachetomcat>= 11.0.0 < 11.0.2211.0.22
apachetomcat7.0.0 – 7.0.109
apachetomcat8.5.0 – 8.5.100
apachetomcat>= 9.0.0 < 9.0.1189.0.118
apache_software_foundationapache_tomcat10.1.0-M1 – 10.1.54
apache_software_foundationapache_tomcat11.0.0-M1 – 11.0.21
apache_software_foundationapache_tomcat7.0.0 – 7.0.109
apache_software_foundationapache_tomcat8.5.0 – 8.5.100
apache_software_foundationapache_tomcat9.0.0.M1 – 9.0.117
debianjss
debiantomcat10
devspacesserver-rhel9
redhat-pki_10jss
ubuntutomcat10
ubuntutomcat11
ubuntutomcat6
ubuntutomcat7
ubuntutomcat8
ubuntutomcat9

Detection & IOCsextracted from sources · hover to see the quote

  • When multiple security constraints define an HTTP method constraint for the same URL extension pattern, Apache Tomcat only applies the first method constraint — subsequent constraints are silently ignored, allowing authorization bypass.
  • Monitor for unexpected successful HTTP requests to URL extensions that should be protected by security constraints, particularly where multiple method constraints exist for the same extension in web.xml.
  • A remote attacker could use this to bypass authorization restrictions — look for access to restricted resources without proper authentication/authorization in Tomcat access logs.
  • ·Vulnerability is only triggered when multiple security constraints define HTTP method constraints for the same URL extension pattern in web.xml. Single-constraint configurations are not affected.
  • ·Affected Apache Tomcat version ranges: 11.0.0-M1 through 11.0.21, 10.1.0-M1 through 10.1.54, 9.0.0.M1 through 9.0.117, 8.5.0 through 8.5.100, 7.0.0 through 7.0.109. Fixed in 11.0.22, 10.1.55, 9.0.118.
  • ·Multiple Red Hat product packages (JBoss Web Server, JBoss EAP, Fuse, Single Sign-On, Process Automation, OpenShift Dev Spaces, etc.) embed the affected tomcat-coyote component but fixes are deferred — detection should cover these deployments as well.

CVSS provenance

nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
vendor_ubuntu9.8CRITICAL
vendor_redhat9.1CRITICAL
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