Description
Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve component of Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.20, from 10.1.0-M1 through 10.1.53, from 9.0.40 through 9.0.116. Users are recommended to upgrade to version 11.0.21, 10.1.54 or 9.0.117 , which fix the issue.
Affected products
apache: tomcat
References2
- lists.apache.org/thread/j1w7304yonlr8vo1tkb5nfs7od1y228b Mailing ListVendor Advisory
- www.openwall.com/lists/oss-security/2026/04/09/26 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:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 41 · as of 12 November 2026
- CWE
- CWE-116
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