Description
Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat via invalid chunk extension. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.18, from 10.1.0-M1 through 10.1.52, from 9.0.0.M1 through 9.0.115, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other, unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.20, 10.1.52 or 9.0.116, which fix the issue.
Affected products
apache: tomcat
References2
- lists.apache.org/thread/2c682qnlg2tv4o5knlggqbl9yc2gb5sn Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2026/04/09/20 Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 1% percentile: 54 · as of 12 November 2026
- CWE
- CWE-444
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