CVE-2018-1336: An improper handing of overflow in the UTF-8 decoder with supplementary characters can lead to an infinite...

Security readout for executives and security teams

Apache Tomcat had a UTF-8 decoding bug where certain supplementary characters could make the decoder loop indefinitely, creating a denial-of-service condition. This matters most for organizations running affected Tomcat versions that support public or business-critical applications. Exposure is limited to Apache Tomcat deployments in the listed affected ranges. Public-facing Tomcat services and internal systems with high availability requirements should be prioritized. Distribution-managed Tomcat packages should be checked against the relevant Ubuntu, Debian, or Red Hat advisories. Treat this as a service-availability risk, not a data-theft issue based on the supplied evidence. Patch affected Tomcat systems through normal urgent maintenance, with higher priority for externally reachable or revenue-impacting applications. Mitigation focus: Upgrade Apache Tomcat to a version outside the affected ranges.; Apply relevant vendor package updates from Ubuntu, Debian, Red Hat, or Apache guidance.; Prioritize internet-facing and business-critical Tomcat services..

Prepared

Jun 7, 2026, 05:54 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.