Description
Incorrect Authorization vulnerability in Apache Tomcat's FORM authentication process allows the bypassing of a security constraint that limits user has access to a resource POST but not GET. 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, from 7.0.0 through 7.0.109. 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 fixes the issue.
Affected products
apache: tomcat
References2
- lists.apache.org/thread/x1y2lfsgzxwzc456f8954vbvgn03zhd7 Vendor AdvisoryMailing List
- www.openwall.com/lists/oss-security/2026/08/26/7 Third Party AdvisoryMailing List
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 1% percentile: 51 · as of 9 November 2026
- CWE
- CWE-863
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