Description
Off-by-one Error vulnerability in Apache Tomcat impacting the [N] flag on the rewrite valves causes rewrite processing to restart at the second rule rather than the first rule. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.24, from 10.1.0-M1 through 10.1.57, from 9.0.0.M1 through 9.0.120. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.25, 10.1.58 or 9.0.121 which fix the issue.
Affected products
apache: tomcat
References2
- lists.apache.org/thread/st1dx1zyn5y7ny2s0sscmh6lrv3worr4 Vendor AdvisoryMailing List
- www.openwall.com/lists/oss-security/2026/08/26/5 Third Party AdvisoryMailing List
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:N/A:H - EPSS — exploit probability
- 1% percentile: 53 · as of 9 November 2026
- CWE
- CWE-193
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