CVE-2026-34483
highpriority · track · 0EPSS 0.005 · 40 %ileDEEURUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (57)
Products and version ranges known to be affected.
- IBM Power Hardware Management Consoleall versionscert_bundDEcpe:/a:ibm:hardware_management_console:-
advisories (4)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-1038Apache Tomcat und Tomcat Native: Mehrere SchwachstellenDeutsch2026-04-09csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Apache Tomcat ausnutzen, um Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren, vertrauliche Informationen offenzulegen, Open-Redirect-Angriffe durchzuführen und andere, nicht näher spezifizierte Angriffe auszuführen.
- WID-SEC-W-2026-1608Atlassian Produkte (Bamboo, Bitbucket, Confluence, Crucible, Fisheye und Jira): Mehrere SchwachstellenDeutsch2026-05-19csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Atlassian Bitbucket, Atlassian Confluence, Atlassian Crucible, Atlassian Fisheye und Atlassian Jira ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um einen Cross-Site Scripting Angriff durchzuführen, und um Sicherheitsvorkehrungen zu umgehen.
- GHSA-rv64-5gf8-9qq8Apache Tomcat has an Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve2026-04-09ghsa · osvUS
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.
- BIT-tomcat-2026-34483Apache Tomcat: Incomplete escaping of JSON access logs2026-09-11vendor · osvUS
Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve component of Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0 through 11.0.20, from 10.1.0 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.
also known as (6)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://lists.apache.org/thread/j1w7304yonlr8vo1tkb5nfs7od1y228bcnnvd
- https://tomcat.apache.org/download-11.cgiPatchcnnvd
- https://vigilance.fr/vulnerability/Apache-Tomcat-four-vulnerabilities-dated-09-04-2026-50413cnnvd
- https://lists.apache.org/thread/j1w7304yonlr8vo1tkb5nfs7od1y228benisa_euvd
- http://www.openwall.com/lists/oss-security/2026/04/09/26Mailing ListThird Party Advisorynvd
- https://lists.apache.org/thread/j1w7304yonlr8vo1tkb5nfs7od1y228bMailing ListVendor Advisorynvd
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