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TI-2025-33451 Aliases CVE-2025-53506GHSA-25xr-qj8w-c4vf

Apache Tomcat: DoS via excessive h2 streams at connection start

Priority MEDIUM 43CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 15 fixed, 4 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-400.

Summary

Uncontrolled Resource Consumption vulnerability in Apache Tomcat if an HTTP/2 client did not acknowledge the initial settings frame that reduces the maximum permitted concurrent streams. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.8, from 10.1.0-M1 through 10.1.42, from 9.0.0.M1 through 9.0.106. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.0 through 8.5.100. Other EOL versions may also be affected. Users are recommended to upgrade to version 11.0.9, 10.1.43 or 9.0.107, which fix the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02129 82nd percentileScored 2026-11-07
Fix Partial org.apache.tomcat:tomcat-coyote (Maven): 11.0.9, 10.1.43, 9.0.107org.apache.tomcat.embed:tomcat-embed-core (Maven): 9.0.107, 10.1.43, 11.0.9Red Hat: 11 advisoriesRed Hat: 15 fixed, 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApacheApache Tomcat11.0.0-M1 – 11.0.8; 10.1.0-M1 – 10.1.42; 9.0.0.M1 – 9.0.106; 8.5.0 – 8.5.100—No fix listedCNA
—org.apache.tomcat:tomcat-coyote (Maven)11.0.0-M1 to before 11.0.911.0.9Patch availableGHSA-25xr-qj8w-c4vf
—org.apache.tomcat:tomcat-coyote (Maven)10.1.0-M1 to before 10.1.4310.1.43Patch availableGHSA-25xr-qj8w-c4vf
—org.apache.tomcat:tomcat-coyote (Maven)9.0.0.M1 to before 9.0.1079.0.107Patch availableGHSA-25xr-qj8w-c4vf
—org.apache.tomcat:tomcat-coyote (Maven)8.5.0 – 8.5.100—No fix listedGHSA-25xr-qj8w-c4vf
—org.apache.tomcat.embed:tomcat-embed-core (Maven)8.5.0 – 8.5.100—No fix listedGHSA-25xr-qj8w-c4vf
—org.apache.tomcat.embed:tomcat-embed-core (Maven)9.0.0.M1 to before 9.0.1079.0.107Patch availableGHSA-25xr-qj8w-c4vf
—org.apache.tomcat.embed:tomcat-embed-core (Maven)10.1.0-M1 to before 10.1.4310.1.43Patch availableGHSA-25xr-qj8w-c4vf
—org.apache.tomcat.embed:tomcat-embed-core (Maven)11.0.0-M1 to before 11.0.911.0.9Patch availableGHSA-25xr-qj8w-c4vf
  • Apache Tomcat VendorApache Affected 11.0.0-M1 – 11.0.8; 10.1.0-M1 – 10.1.42; 9.0.0.M1 – 9.0.106; 8.5.0 – 8.5.100 Fixed in — No fix listed CNA
  • org.apache.tomcat:tomcat-coyote (Maven) Vendor— Affected 11.0.0-M1 to before 11.0.9 Fixed in 11.0.9 Patch available GHSA-25xr-qj8w-c4vf
  • org.apache.tomcat:tomcat-coyote (Maven) Vendor— Affected 10.1.0-M1 to before 10.1.43 Fixed in 10.1.43 Patch available GHSA-25xr-qj8w-c4vf
  • org.apache.tomcat:tomcat-coyote (Maven) Vendor— Affected 9.0.0.M1 to before 9.0.107 Fixed in 9.0.107 Patch available GHSA-25xr-qj8w-c4vf
  • org.apache.tomcat:tomcat-coyote (Maven) Vendor— Affected 8.5.0 – 8.5.100 Fixed in — No fix listed GHSA-25xr-qj8w-c4vf
  • org.apache.tomcat.embed:tomcat-embed-core (Maven) Vendor— Affected 8.5.0 – 8.5.100 Fixed in — No fix listed GHSA-25xr-qj8w-c4vf
  • org.apache.tomcat.embed:tomcat-embed-core (Maven) Vendor— Affected 9.0.0.M1 to before 9.0.107 Fixed in 9.0.107 Patch available GHSA-25xr-qj8w-c4vf
  • org.apache.tomcat.embed:tomcat-embed-core (Maven) Vendor— Affected 10.1.0-M1 to before 10.1.43 Fixed in 10.1.43 Patch available GHSA-25xr-qj8w-c4vf
  • org.apache.tomcat.embed:tomcat-embed-core (Maven) Vendor— Affected 11.0.0-M1 to before 11.0.9 Fixed in 11.0.9 Patch available GHSA-25xr-qj8w-c4vf

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*9.0.0 – 9.0.106; 10.1.0 – 10.1.42; 11.0.0 – 11.0.8VulnerableApache
  • cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:* Versions 9.0.0 – 9.0.106; 10.1.0 – 10.1.42; 11.0.0 – 11.0.8 Vulnerable ·Apache

Remediation

  • Fix · GHSA-25xr-qj8w-c4vf org.apache.tomcat:tomcat-coyote (Maven) Fixed in 11.0.9 Advisory →
  • Fix · GHSA-25xr-qj8w-c4vf org.apache.tomcat:tomcat-coyote (Maven) Fixed in 10.1.43 Advisory →
  • Fix · GHSA-25xr-qj8w-c4vf org.apache.tomcat:tomcat-coyote (Maven) Fixed in 9.0.107 Advisory →
  • Fix · GHSA-25xr-qj8w-c4vf org.apache.tomcat.embed:tomcat-embed-core (Maven) Fixed in 9.0.107 Advisory →
  • Fix · GHSA-25xr-qj8w-c4vf org.apache.tomcat.embed:tomcat-embed-core (Maven) Fixed in 10.1.43 Advisory →
  • Fix · GHSA-25xr-qj8w-c4vf org.apache.tomcat.embed:tomcat-embed-core (Maven) Fixed in 11.0.9 Advisory →

Red Hat 11 advisories

  • RHSA-2025:14180 Released 2025-08-20 · Red Hat rating Important
    tomcat security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.4) tomcat-1:9.0.87-1.el9_4.6, tomcat-admin-webapps-1:9.0.87-1.el9_4.6, tomcat-docs-webapp-1:9.0.87-1.el9_4.6 +5
  • RHSA-2025:14181 Released 2025-08-20 · Red Hat rating Important
    tomcat security update
    • Red Hat Enterprise Linux AppStream (v. 9) tomcat-1:9.0.87-3.el9_6.3, tomcat-admin-webapps-1:9.0.87-3.el9_6.3, tomcat-docs-webapp-1:9.0.87-3.el9_6.3 +5
  • RHSA-2025:14183 Released 2025-08-20 · Red Hat rating Important
    tomcat security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) tomcat-1:9.0.87-1.el9_2.6, tomcat-admin-webapps-1:9.0.87-1.el9_2.6, tomcat-docs-webapp-1:9.0.87-1.el9_2.6 +5
Show 8 more Red Hat advisories
  • RHSA-2025:14177 Released 2025-08-20 · Red Hat rating Important
    tomcat security update
    • Red Hat Enterprise Linux AppStream (v. 8) tomcat-1:9.0.87-1.el8_10.6, tomcat-admin-webapps-1:9.0.87-1.el8_10.6, tomcat-docs-webapp-1:9.0.87-1.el8_10.6 +5
  • RHSA-2025:14182 Released 2025-08-20 · Red Hat rating Important
    tomcat security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) tomcat-1:9.0.87-1.el8_8.7, tomcat-admin-webapps-1:9.0.87-1.el8_8.7, tomcat-docs-webapp-1:9.0.87-1.el8_8.7 +5
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) tomcat-1:9.0.87-1.el8_8.7, tomcat-admin-webapps-1:9.0.87-1.el8_8.7, tomcat-docs-webapp-1:9.0.87-1.el8_8.7 +5
  • RHSA-2025:14179 Released 2025-08-20 · Red Hat rating Important
    tomcat security update
    • Red Hat Enterprise Linux AppStream (v. 10) tomcat-1:10.1.36-1.el10_0.2, tomcat-admin-webapps-1:10.1.36-1.el10_0.2, tomcat-docs-webapp-1:10.1.36-1.el10_0.2 +5
  • RHSA-2025:14178 Released 2025-08-20 · Red Hat rating Important
    tomcat9 security update
    • Red Hat Enterprise Linux AppStream (v. 10) tomcat9-1:9.0.87-5.el10_0.3, tomcat9-admin-webapps-1:9.0.87-5.el10_0.3, tomcat9-docs-webapp-1:9.0.87-5.el10_0.3 +5
  • RHSA-2025:11742 Released 2025-07-30 · Red Hat rating Moderate
    Red Hat JBoss Web Server 6.1.1 release and security update
    • Red Hat JBoss Web Server 6.1.1
  • RHSA-2025:11741 Released 2025-07-30 · Red Hat rating Moderate
    Red Hat JBoss Web Server 6.1.1 release and security update
    • Red Hat JBoss Web Server 6.1 for RHEL 10 jws6-tomcat-10.1.36-7.redhat_00008.1.el10jws, jws6-tomcat-admin-webapps-10.1.36-7.redhat_00008.1.el10jws, jws6-tomcat-docs-webapp-10.1.36-7.redhat_00008.1.el10jws +7
    • Red Hat JBoss Web Server 6.1 for RHEL 8 jws6-tomcat-10.1.36-7.redhat_00008.1.el8jws, jws6-tomcat-admin-webapps-10.1.36-7.redhat_00008.1.el8jws, jws6-tomcat-docs-webapp-10.1.36-7.redhat_00008.1.el8jws +7
    • Red Hat JBoss Web Server 6.1 for RHEL 9 jws6-tomcat-10.1.36-7.redhat_00008.1.el9jws, jws6-tomcat-admin-webapps-10.1.36-7.redhat_00008.1.el9jws, jws6-tomcat-docs-webapp-10.1.36-7.redhat_00008.1.el9jws +7
  • RHSA-2025:11696 Released 2025-07-28 · Red Hat rating Moderate
    Red Hat JBoss Web Server 5.8.5 release and security update
    • Red Hat JBoss Web Server 5.8.5
  • RHSA-2025:11695 Released 2025-07-28 · Red Hat rating Moderate
    Red Hat JBoss Web Server 5.8.5 release and security update
    • Red Hat JBoss Web Server 5.8 for RHEL 7 Server jws5-tomcat-9.0.87-12.redhat_00011.1.el7jws, jws5-tomcat-admin-webapps-9.0.87-12.redhat_00011.1.el7jws, jws5-tomcat-docs-webapp-9.0.87-12.redhat_00011.1.el7jws +9
    • Red Hat JBoss Web Server 5.8 for RHEL 8 jws5-tomcat-9.0.87-12.redhat_00011.1.el8jws, jws5-tomcat-admin-webapps-9.0.87-12.redhat_00011.1.el8jws, jws5-tomcat-docs-webapp-9.0.87-12.redhat_00011.1.el8jws +7
    • Red Hat JBoss Web Server 5.8 for RHEL 9 jws5-tomcat-9.0.87-12.redhat_00011.1.el9jws, jws5-tomcat-admin-webapps-9.0.87-12.redhat_00011.1.el9jws, jws5-tomcat-docs-webapp-9.0.87-12.redhat_00011.1.el9jws +7

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:14178, RHSA-2025:14179
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2025:14177
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:14181
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2025:14182
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2025:14183
Red Hat Enterprise Linux AppStream EUS (v.9.4)Fixed RHSA-2025:14180
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2025:14182
Red Hat JBoss Web Server 5.8 for RHEL 7 ServerFixed RHSA-2025:11695
Red Hat JBoss Web Server 5.8 for RHEL 8Fixed RHSA-2025:11695
Red Hat JBoss Web Server 5.8 for RHEL 9Fixed RHSA-2025:11695
Red Hat JBoss Web Server 5.8.5Fixed RHSA-2025:11696
Red Hat JBoss Web Server 6.1 for RHEL 10Fixed RHSA-2025:11741
Red Hat JBoss Web Server 6.1 for RHEL 8Fixed RHSA-2025:11741
Red Hat JBoss Web Server 6.1 for RHEL 9Fixed RHSA-2025:11741
Red Hat JBoss Web Server 6.1.1Fixed RHSA-2025:11742

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-53506
  2. 2026-10-03 Alias added: GHSA-25xr-qj8w-c4vf
  3. 2026-10-09 Fix available: RHSA-2025:11742 · Red Hat
  4. 2026-11-05 Fix available: Red Hat JBoss Web Server 6.1.1 · Red Hat

References

Advisory 2

Other 6

  • TI-2025-18529 Apache Tomcat: Potential RCE and/or information disclosure and/or information corruption with partial PUT KEVCVSS 3.1CRITICAL 10.0
  • TI-2020-01862 Improper privilege management in Apache Tomcat KEVCVSS 3.1CRITICAL 9.8
  • TI-2016-07192 Improper access control in Apache Tomcat KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-09342 Unrestricted file upload in Apache Tomcat KEVCVSS 3.1HIGH 8.1
  • TI-2017-09340 Unrestricted file upload in Apache Tomcat KEVCVSS 3.1HIGH 8.1
  • TI-2026-26741 Apache Tomcat: Fix for CVE-2026-29146 allowed bypass of EncryptInterceptor KEVCVSS 3.1HIGH 7.5
See all 273 →

Sources

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