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Medium

Apache Tomcat Denial of Service via invalid HTTP priority header

  • Disclosed: 28.04.2025
  • Updated: 11.10.2026 13:20

Improper Input Validation vulnerability in Apache Tomcat. Incorrect error handling for some invalid HTTP priority headers resulted in incomplete clean-up of the failed request which created a memory leak. A large number of such requests could trigger an OutOfMemoryException resulting in a denial of service.

This issue affects Apache Tomcat: from 9.0.76 through 9.0.102, from 10.1.10 through 10.1.39, from 11.0.0-M2 through 11.0.5. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.90 though 8.5.100.

Users are recommended to upgrade to version 9.0.104, 10.1.40 or 11.0.6 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 >= 9.0.76, < 9.0.104, >= 10.1.10, < 10.1.40, >= 11.0.0-M2, < 11.0.6, >= 8.5.0, <= 8.5.100 9.0.104, 10.1.40, 11.0.6
Java / Kotlin (Maven) org.apache.tomcat:tomcat-coyote >= 9.0.76, < 9.0.104, >= 10.1.10, < 10.1.40, >= 11.0.0-M2, < 11.0.6, >= 8.5.0, <= 8.5.100 9.0.104, 10.1.40, 11.0.6

References

CVSS score -
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Weakness (CWE)
CWE-459, CWE-460
Platform
Java / Kotlin (Maven)
Package
org.apache.tomcat.embed:tomcat-embed-core, org.apache.tomcat:tomcat-coyote
Disclosed
28.04.2025
Updated
11.10.2026 13:20

Sources and licenses

OSV / GitHub Advisory Database - GHSA-3p2h-wqq4-wf4h - CC BY 4.0

Vulnerability history: org.apache.tomcat:tomcat-coyote

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 (33) in the archive
Total entries
33
First → latest
06.2020 05.2026
Without a fix
0
Exploited in attacks
1

Severity breakdown

  • Critical 2
  • High 17
  • Medium 13
  • Low 1

Disclosures per year

Severity:
  1. Apache Tomcat - HTTP/2 request headers not validated
    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
  2. Apache Tomcat has an HTTP Request/Response Smuggling vulnerability
    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
  3. Apache Tomcat: Configured cipher preference order not preserved
    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
  4. Apache Tomcat has an Improper Input Validation vulnerability
    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
  5. Apache Tomcat Improper Resource Shutdown or Release vulnerability
    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
  6. Apache Tomcat Coyote vulnerable to Denial of Service via excessive HTTP/2 streams
    High · 7.5 CVE-2025-53506 >= 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
  7. Apache Tomcat Denial of Service via invalid HTTP priority header this entry
    Medium CVE-2025-31650 >= 9.0.76, < 9.0.104, >= 10.1.10, < 10.1.40, >= 11.0.0-M2, < 11.0.6, >= 8.5.0, <= 8.5.100 9.0.104, 10.1.40, 11.0.6
  8. Apache Tomcat Allocation of Resources Without Limits or Throttling vulnerability
    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
  9. Apache Tomcat - Denial of Service
    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
  10. Apache Tomcat Improper Input Validation vulnerability
    High · 7.5 CVE-2023-46589 >= 11.0.0-M1, < 11.0.0-M11 11.0.0-M11
  11. Apache Tomcat - Fix for CVE-2023-24998 was incomplete
    High · 7.5 CVE-2023-28709 >= 8.5.85, < 8.5.88 8.5.88
  12. Apache Tomcat vulnerable to information leak
    High · 7.5 CVE-2023-34981 >= 8.5.88, < 8.5.89 8.5.89
  13. Apache Commons FileUpload denial of service vulnerability
    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
  14. Apache Tomcat may reject request containing invalid Content-Length header
    High · 7.5 CVE-2022-42252 >= 9.0.0-M1, < 9.0.68, >= 10.0.0-M1, < 10.0.27, >= 10.1.0-M1, < 10.1.1 9.0.68, 10.0.27, 10.1.1
  15. Expected Behavior Violation in Apache Tomcat
    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
  16. Improper Input Validation in Apache Tomcat
    High · 7.1 CVE-2016-6816 >= 9.0.0.M1, < 9.0.0.M12, >= 8.5.0, < 8.5.8, >= 8.0.0RC1, < 8.0.39, >= 7.0.0, < 7.0.73, >= 6.0.0, < 6.0.48 9.0.0.M12, 8.5.8, 8.0.39, 7.0.73, 6.0.48
  17. Exposure of Sensitive Information to an Unauthorized Actor in Apache Tomcat
    High · 7.5 CVE-2020-17527 >= 10.0.0-M1, < 10.0.0-M10, >= 9.0.0-M1, < 9.0.40, >= 8.5.0, < 8.5.60 10.0.0-M10, 9.0.40, 8.5.60
  18. Improper Restriction of Operations within the Bounds of a Memory Buffer in Apache Tomcat
    High · 7.5 CVE-2020-13934 >= 10.0.0-M1, < 10.0.0-M6, >= 9.0.0.M5, < 9.0.36, >= 8.5.1, < 8.5.56 10.0.0-M6, 9.0.36, 8.5.56
  19. Exposure of Sensitive Information to an Unauthorized Actor in Apache Tomcat
    High · 7.5 CVE-2021-25122 >= 10.0.0-M1, < 10.0.2 10.0.2
  20. Apache Tomcat Denial of Service vulnerability
    High · 7.5 CVE-2019-0199 >= 9.0.0, < 9.0.16, >= 8.0.0, < 8.5.38 9.0.16, 8.5.38

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