CVE-2026-59313

A flaw was found in the Spring MVC functional web framework. This vulnerability allows for stream corruption when applications use Server-Sent Events (SSE), a technology for pushing real-time updates from a server to a client. This could lead to unreliable data delivery and impact the integrity of information presented to users.

A flaw was found in the Spring Framework functional web framework's Server-Sent Events (SSE) implementation. When plain-text data that an attacker controls is sent through an SSE ServerResponse and contains a bare carriage return (\r), the text can break out of its data field and be interpreted by the browser as new SSE fields. This vulnerability affects applications using RouterFunction and ServerResponse.sse() to send streaming plain-text data. Applications using JSON-serialized events via HttpMessageConverter or annotated controllers with SseEmitter are not affected, as these implementations already escape carriage returns.

Red Hat ships vulnerable versions of Spring Framework in JBoss Fuse 7 (Extended Lifecycle Support), Red Hat OpenShift Dev Spaces, Red Hat build of Apache Camel for Quarkus (Hawtio), and Subscription Services components.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

There is no mitigation available for this issue. Apply updates as they become available from Red Hat product teams. As a temporary workaround, ensure that Server-Sent Events use structured formats like JSON instead of plain text for all user-controlled data.