High

Apache Tomcat Coyote vulnerable to Denial of Service via excessive HTTP/2 streams

  • Disclosed: 10.07.2025
  • Updated: 11.10.2026 13:20

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.

Users are recommended to upgrade to version 11.0.9, 10.1.43 or 9.0.107, which fix the issue.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Java / Kotlin (Maven) org.apache.tomcat.embed:tomcat-embed-core >= 8.5.0, <= 8.5.100, >= 9.0.0.M1, < 9.0.107, >= 10.1.0-M1, < 10.1.43, >= 11.0.0-M1, < 11.0.9 9.0.107, 10.1.43, 11.0.9
Java / Kotlin (Maven) org.apache.tomcat:tomcat-coyote >= 11.0.0-M1, < 11.0.9, >= 10.1.0-M1, < 10.1.43, >= 9.0.0.M1, < 9.0.107, >= 8.5.0, <= 8.5.100 11.0.9, 10.1.43, 9.0.107

References

CVSS score 7.5/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE)
CWE-400
Platform
Java / Kotlin (Maven)
Package
org.apache.tomcat.embed:tomcat-embed-core, org.apache.tomcat:tomcat-coyote
Disclosed
10.07.2025
Updated
11.10.2026 13:20

Sources and licenses

OSV / GitHub Advisory Database - GHSA-25xr-qj8w-c4vf - CC BY 4.0

Vulnerability history: org.apache.tomcat.embed:tomcat-embed-core

All published vulnerabilities of this package (Java / Kotlin (Maven)), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (77) in the archive
Total entries
77
First → latest
10.2018 08.2026
Without a fix
0
Exploited in attacks
5

Severity breakdown

  • Critical 11
  • High 36
  • Medium 25
  • Low 5

Disclosures per year

  1. 2018: 8
  2. 2019: 5
  3. 2020: 5
  4. 2021: 3
  5. 2022: 7
  6. 2023: 9
  7. 2024: 7
  8. 2025: 15
  9. 2026: 18
Severity:
  1. Critical · 9.8 CVE-2026-65905 >= 11.0.0-M1, < 11.0.25, >= 10.1.0-M1, < 10.1.58, >= 9.0.0.M1, < 9.0.121, >= 8.5.0, <= 8.5.100, >= 7.0.30, <= 7.0.109 11.0.25, 10.1.58, 9.0.121
  2. Critical · 9.1 CVE-2026-65182 >= 11.0.0-M1, < 11.0.25, >= 10.1.0-M1, < 10.1.58, >= 9.0.0-M1, < 9.0.121, >= 8.5.0, <= 8.5.100, >= 7.0.0, <= 7.0.109 11.0.25, 10.1.58, 9.0.121
  3. Critical · 9.1 CVE-2026-68525 >= 11.0.0-M1, < 11.0.25, >= 10.1.0-M1, < 10.1.58, >= 9.0.0-M1, < 9.0.121, >= 8.5.0, <= 8.5.100, >= 7.0.0, <= 7.0.109 11.0.25, 10.1.58, 9.0.121
  4. High · 7.5 CVE-2026-41284 < 9.0.118, >= 10.1.0-M1, < 10.1.55, >= 11.0.0-M1, < 11.0.22 9.0.118, 10.1.55, 11.0.22
  5. Critical · 9.8 CVE-2026-43512 < 9.0.118, >= 10.1.0-M1, < 10.1.55, >= 11.0.0-M1, < 11.0.22 9.0.118, 10.1.55, 11.0.22
  6. High · 7.5 CVE-2026-43513 < 9.0.118, >= 10.1.0-M1, < 10.1.55, >= 11.0.0-M1, < 11.0.22 9.0.118, 10.1.55, 11.0.22
  7. Critical · 9.1 CVE-2026-43515 < 9.0.118, >= 10.1.0-M1, < 10.1.55, >= 11.0.0-M1, < 11.0.22 9.0.118, 10.1.55, 11.0.22
  8. High · 7.3 CVE-2026-42498 < 9.0.118, >= 10.1.0-M1, < 10.1.55, >= 11.0.0-M1, < 11.0.22 9.0.118, 10.1.55, 11.0.22
  9. Critical · 9.8 CVE-2026-41293 >= 8.5.0, < 9.0.118, >= 10.1.0-M1, < 10.1.55, >= 11.0.0-M1, < 11.0.22 9.0.118, 10.1.55, 11.0.22
  10. High · 7.5 CVE-2026-34487 >= 9.0.13, < 9.0.117, >= 10.1.0-M1, < 10.1.54, >= 11.0.0-M1, < 11.0.21 9.0.117, 10.1.54, 11.0.21
  11. High · 7.5 CVE-2026-34483 >= 9.0.40, < 9.0.116, >= 10.1.0-M1, < 10.1.54, >= 11.0.0-M1, < 11.0.21 9.0.116, 10.1.54, 11.0.21
  12. High · 7.5 CVE-2026-24880 >= 7.0.0, < 9.0.116, >= 10.1.0-M1, < 10.1.52, >= 11.0.0-M1, < 11.0.20 9.0.116, 10.1.52, 11.0.20
  13. High · 7.5 CVE-2026-29129 >= 9.0.114, < 9.0.116, >= 10.1.51, < 10.1.53, >= 11.0.16, < 11.0.20 9.0.116, 10.1.53, 11.0.20
  14. High · 7.5 CVE-2026-24734 >= 11.0.0-M1, < 11.0.18, >= 10.1.0-M7, < 10.1.52, >= 9.0.83, < 9.0.115 11.0.18, 10.1.52, 9.0.115
  15. High · 7.5 CVE-2025-55752 >= 11.0.0-M1, < 11.0.11, >= 10.1.0-M1, < 10.1.45, >= 9.0.0-M11, < 9.0.109, >= 8.5.6, <= 8.5.100 11.0.11, 10.1.45, 9.0.109
  16. High · 7.5 CVE-2025-48989 >= 11.0.0-M1, < 11.0.10, >= 10.1.0-M1, < 10.1.44, >= 9.0.0.M1, < 9.0.108 11.0.10, 10.1.44, 9.0.108
  17. Apache Tomcat Coyote vulnerable to Denial of Service via excessive HTTP/2 streams this entry
    High · 7.5 CVE-2025-53506 >= 8.5.0, <= 8.5.100, >= 9.0.0.M1, < 9.0.107, >= 10.1.0-M1, < 10.1.43, >= 11.0.0-M1, < 11.0.9 9.0.107, 10.1.43, 11.0.9
  18. High · 7.5 CVE-2025-52520 >= 11.0.0-M1, < 11.0.9, >= 10.1.0-M1, < 10.1.43, >= 9.0.0.M1, < 9.0.107, >= 8.5.0, <= 8.5.100 11.0.9, 10.1.43, 9.0.107
  19. High · 7.5 CVE-2025-48988 >= 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 11.0.8, 10.1.42, 9.0.106
  20. Critical · 9.8 Exploited in attacks CVE-2025-24813 >= 11.0.0-M1, < 11.0.3, >= 10.1.0-M1, < 10.1.35, >= 9.0.0.M1, < 9.0.99, >= 8.5.0, <= 8.5.100 11.0.3, 10.1.35, 9.0.99
  21. High CVE-2024-56337 >= 11.0.0-M1, < 11.0.2, >= 10.1.0-M1, < 10.1.34, >= 9.0.0.M1, < 9.0.98 11.0.2, 10.1.34, 9.0.98
  22. High · 9.8 CVE-2024-50379 >= 11.0.0-M1, < 11.0.2, >= 10.1.0-M1, < 10.1.34, >= 9.0.0.M1, < 9.0.98, >= 8.5.0, <= 8.5.100 11.0.2, 10.1.34, 9.0.98
  23. High · 8.6 CVE-2024-38286 >= 11.0.0-M1, < 11.0.0-M21, >= 10.1.0-M1, < 10.1.25, >= 9.0.13, < 9.0.90, >= 8.5.35, <= 8.5.100, >= 7.0.92, <= 7.0.109 11.0.0-M21, 10.1.25, 9.0.90
  24. High · 7.5 CVE-2024-34750 >= 11.0.0-M1, < 11.0.0-M21, >= 10.1.0-M1, < 10.1.25, >= 9.0.0-M1, < 9.0.90, >= 8.5.0, <= 8.5.100 11.0.0-M21, 10.1.25, 9.0.90
  25. High · 7.5 CVE-2023-46589 >= 11.0.0-M1, < 11.0.0-M11, >= 10.1.0-M1, < 10.1.16, >= 9.0.0-M1, < 9.0.83, >= 8.5.0, < 8.5.96 11.0.0-M11, 10.1.16, 9.0.83, 8.5.96
  26. High · 7.5 CVE-2023-28709 >= 11.0.0-M2, < 11.0.0-M5, >= 10.1.5, < 10.1.8, >= 9.0.71, < 9.0.74 11.0.0-M5, 10.1.8, 9.0.74
  27. High · 7.5 CVE-2023-34981 >= 11.0.0-M5, < 11.0.0-M6, >= 10.1.8, < 10.1.9, >= 9.0.74, < 9.0.75 11.0.0-M6, 10.1.9, 9.0.75
  28. High · 7.5 CVE-2023-24998 >= 10.1.0-M1, < 10.1.5, >= 11.0.0-M2, < 11.0.0-M5, >= 8.5.85, < 8.5.88, >= 9.0.0-M1, < 9.0.71 10.1.5, 11.0.0-M5, 8.5.88, 9.0.71
  29. High · 7.5 CVE-2022-45143 >= 8.5.83, < 8.5.84, >= 9.0.40, < 9.0.69, >= 10.1.0, < 10.1.2 8.5.84, 9.0.69, 10.1.2
  30. High · 7.5 CVE-2022-42252 >= 8.5.0, < 8.5.83, >= 9.0.0-M1, < 9.0.68, >= 10.0.0-M1, < 10.0.27, >= 10.1.0-M1, < 10.1.1 8.5.83, 9.0.68, 10.0.27, 10.1.1
  31. High · 8.1 Exploited in attacks CVE-2017-12617 >= 9.0.0.M1, < 9.0.1, >= 8.5.0, < 8.5.23, >= 8.0.0-RC1, < 8.0.47, >= 7.0.0, < 7.0.82 9.0.1, 8.5.23, 8.0.47, 7.0.82
  32. Critical · 9.8 CVE-2017-5651 >= 9.0.0.M1, < 9.0.0.M19, >= 8.5.0, < 8.5.13 9.0.0.M19, 8.5.13
  33. Critical · 9.1 CVE-2017-5648 >= 9.0.0.M1, < 9.0.0.M18, >= 8.5.0, < 8.5.13, >= 8.0.0, < 8.0.42, >= 7.0.0, < 7.0.76 9.0.0.M18, 8.5.13, 8.0.42, 7.0.76
  34. High · 7.5 CVE-2020-11996 >= 10.0.0-M1, < 10.0.0-M5, >= 9.0.0.M1, < 9.0.35, >= 8.5.0, < 8.5.55 10.0.0-M5, 9.0.35, 8.5.55
  35. High · 7.5 CVE-2021-25122 >= 10.0.0-M1, < 10.0.2, >= 9.0.0-M1, < 9.0.43, >= 8.5.0, < 8.5.63 10.0.2, 9.0.43, 8.5.63
  36. High · 7.0 CVE-2021-25329 >= 10.0.0-M1, < 10.0.2, >= 9.0.0, < 9.0.41, >= 8.0.0, < 8.5.61, >= 7.0.0, < 7.0.108 10.0.2, 9.0.41, 8.5.61, 7.0.108
  37. Critical · 9.8 Exploited in attacks CVE-2020-1938 >= 9.0.0, < 9.0.31, >= 8.0.0, < 8.5.51, >= 7.0.0, < 7.0.100 9.0.31, 8.5.51, 7.0.100
  38. High · 7.5 CVE-2019-0199 >= 9.0.0, < 9.0.16, >= 8.0.0, < 8.5.38 9.0.16, 8.5.38
  39. High · 7.0 CVE-2020-9484 >= 10.0.0-M1, < 10.0.0-M5, >= 9.0.0, < 9.0.35, >= 8.0.0, < 8.5.55, >= 7.0.0, < 7.0.104 10.0.0-M5, 9.0.35, 8.5.55, 7.0.104
  40. High · 7.0 CVE-2019-12418 < 7.0.99, >= 8.0.0, < 8.5.49, >= 9.0.0, < 9.0.29 7.0.99, 8.5.49, 9.0.29
  41. High · 7.5 CVE-2019-17563 < 7.0.99, >= 8.0.0, < 8.5.50, >= 9.0.0, < 9.0.30 7.0.99, 8.5.50, 9.0.30
  42. High · 7.5 CVE-2019-10072 >= 9.0.0.M1, < 9.0.20, >= 8.5.0, < 8.5.41 9.0.20, 8.5.41
  43. High · 8.1 CVE-2019-0232 >= 9.0.0.M1, < 9.0.17, >= 8.0.0, < 8.5.40, >= 7.0.0, < 7.0.94 9.0.17, 8.5.40, 7.0.94
  44. High · 7.5 CVE-2018-8034 >= 9.0.0, < 9.0.10, >= 8.5.0, < 8.5.32, >= 8.0.0, < 8.0.53, >= 7.0.35, < 7.0.90 9.0.10, 8.5.32, 8.0.53, 7.0.90
  45. Critical · 9.8 CVE-2018-8014 >= 9.0.0.M1, < 9.0.9, >= 8.5.0, < 8.5.32, >= 8.0.0RC1, < 8.0.53, >= 7.0.41, < 7.0.88 9.0.9, 8.5.32, 8.0.53, 7.0.88
  46. High · 7.5 CVE-2018-1336 >= 9.0.0.M9, < 9.0.8, >= 8.5.0, < 8.5.31, >= 8.0.0RC1, < 8.0.51, >= 7.0.28, < 7.0.87 9.0.8, 8.5.31, 8.0.51, 7.0.87
  47. High · 8.1 Exploited in attacks CVE-2017-12615 >= 7.0.0, < 7.0.79 7.0.79

Know which vulnerabilities affect your application

With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.

Connect your application
DockRay newsletter

Application security in your inbox

Important vulnerabilities, actionable guidance and practical advice for your applications. Choose your technologies and follow what matters to your project.

  • A daily digest of new vulnerabilities, critical ones included.
  • Notifications about important updates.
  • Practical advice on application security and monitoring.

Leave empty to receive updates for every technology.

Free to subscribe. Unsubscribe with one click in any email.