CVE-2026-34483

Apache Tomcat: Incomplete escaping of JSON access logs

State: Published
Severity: 7.5 High
Published: Apr 9, 2026
Updated: Apr 10, 2026
Reserved: Mar 30, 2026

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.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N	CISA-ADP

Weaknesses

CWE-116 Improper Encoding or Escaping of Output

Affected Products

Product	Versions
Apache TomcatApache Software Foundation	11.0.0-M1 through 11.0.20Affected 10.1.0-M1 through 10.1.53Affected 9.0.40 through 9.0.116Affected 8.5.84 through 8.5.100Affected 8.5.83 and earlierNot affected

References

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