CVE-2026-86350criticalCWE-444

CVE-2026-86350: critical vulnerability in Apache Tomcat

Apache Tomcat: Regression in fix for CVE-2026-41293 can trigger request header mix-up

Published

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48Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 9.1epss 0.5%
from disclosure to weapon2 days
Published on NVDSep 23
1st PoC+2d
Inconsistent interpretation of HTTP/2 requests ('HTTP Request/Response smuggling') vulnerability in Apache Tomcat caused by a regression in fix for CVE-2026-41293 can trigger request header mix-up. This issue affects Apache Tomcat: from 11.0.22 through 11.0.25, from 10.1.55 through 10.1.59, from 9.0.118 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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
Apache Software Foundation · Apache Tomcat
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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