Apache Tomcat 10.1.x DoS and policy bypass flaws
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Multiple vulnerabilities in Apache Tomcat 10.1.x allow remote denial of service and security policy bypass; patch to 10.1.59.
The French national CERT (CERT-FR) has published an advisory documenting multiple vulnerabilities affecting Apache Tomcat versions 10.1.x prior to 10.1.59. The flaws permit remote attackers to trigger denial-of-service conditions and bypass security policies implemented within the application server. Apache released patched versions on 20 August 2026 to address these issues.
Defenders running Tomcat 10.1.x should prioritize immediate patching to version 10.1.59 or later. The advisory identifies twelve distinct CVE identifiers associated with this release, indicating a broad set of security defects across the affected version line. The specific attack vectors and technical details of each vulnerability are referenced in the Apache security bulletin and individual CVE records, which should be consulted for detailed mitigation guidance and compatibility information before deploying updates in production environments.
Mentioned in this report
Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1083
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