CVE-2026-34483: CWE-116 Improper Encoding or Escaping of Output in Apache Software Foundation Apache Tomcat
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.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-34483) in Apache Tomcat arises from improper encoding or escaping of output in the JsonAccessLogValve component, classified under CWE-116. It affects multiple Apache Tomcat versions across the 9.x, 10.x, and 11.x branches. The improper output encoding could potentially expose sensitive data or cause other security issues related to output handling. The Apache Software Foundation has released fixed versions (11.0.21, 10.1.54, and 9.0.117) that resolve this vulnerability. No cloud service is involved, and no known active exploits have been reported.
Potential Impact
The vulnerability allows for improper encoding or escaping of output in the JsonAccessLogValve, which can lead to exposure of sensitive information (confidentiality impact is high). There is no impact on integrity or availability reported. The CVSS score of 7.5 reflects a high severity due to the potential confidentiality impact and the fact that the vulnerability is remotely exploitable without privileges or user interaction.
Mitigation Recommendations
A fix is available. Users should upgrade Apache Tomcat to versions 11.0.21, 10.1.54, or 9.0.117 to remediate this vulnerability. No additional mitigation steps are indicated beyond applying the official updates.
CVE-2026-34483: CWE-116 Improper Encoding or Escaping of Output in Apache Software Foundation Apache Tomcat
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-34483) in Apache Tomcat arises from improper encoding or escaping of output in the JsonAccessLogValve component, classified under CWE-116. It affects multiple Apache Tomcat versions across the 9.x, 10.x, and 11.x branches. The improper output encoding could potentially expose sensitive data or cause other security issues related to output handling. The Apache Software Foundation has released fixed versions (11.0.21, 10.1.54, and 9.0.117) that resolve this vulnerability. No cloud service is involved, and no known active exploits have been reported.
Potential Impact
The vulnerability allows for improper encoding or escaping of output in the JsonAccessLogValve, which can lead to exposure of sensitive information (confidentiality impact is high). There is no impact on integrity or availability reported. The CVSS score of 7.5 reflects a high severity due to the potential confidentiality impact and the fact that the vulnerability is remotely exploitable without privileges or user interaction.
Mitigation Recommendations
A fix is available. Users should upgrade Apache Tomcat to versions 11.0.21, 10.1.54, or 9.0.117 to remediate this vulnerability. No additional mitigation steps are indicated beyond applying the official updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-03-30T07:40:44.705Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69d806d21cc7ad14da15a55c
Added to database: 4/9/2026, 8:06:42 PM
Last enriched: 4/17/2026, 12:17:03 PM
Last updated: 5/25/2026, 12:19:38 PM
Views: 186
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