CVE-2026-78437 (GCVE-0-2026-78437)

Vulnerability from cvelistv5 – Published: 2026-09-23 11:26 – Updated: 2026-09-23 18:10
VLAI
Title
Apache Tomcat: HTTP/2 DoS via malformed request
Summary
Incomplete cleanup vulnerability in Apache Tomcat allows a malformed request to potentially (depends on timing) cause one request from another user to fail. This issue affects Apache Tomcat: from 11.0.19 through 11.0.25, from 10.1.53 through 10.1.59, from 9.0.116 through 9.0.121. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-23 16:25 UTC
CWE
Assigner
apache CNA under the mitre root
CNA scorecard B 76/100 over 946 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache Tomcat Affected: 11.0.19 , ≤ 11.0.25 (semver)
Affected: 10.1.53 , ≤ 10.1.59 (semver)
Affected: 9.0.116 , ≤ 9.0.121 (semver)
Unaffected: 0 , ≤ 8.5.100 (semver)
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