CVE-2026-93488 PUBLISHED

Io.netty/netty-codec-http: netty: denial of service via unbounded concurrent spdy streams

Assigner: redhat
Reserved: 18.09.2026 Published: 18.09.2026 Updated: 18.09.2026

A flaw was found in Netty. SpdySessionHandler accepts an unlimited number of concurrent remote-initiated streams because localConcurrentStreams defaults to Integer.MAX_VALUE and the handler provides no API to change it. A remote peer can open a SPDY connection and send a large number of SYN_STREAM frames with FLAG_FIN=0, causing unbounded heap and direct memory allocation that can lead to JVM OutOfMemoryError and a denial of service.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 7.5

Product Status

Vendor Red Hat
Product Red Hat AMQ Broker 7
Versions Default: affected
Vendor Red Hat
Product Red Hat AMQ Clients
Versions Default: affected
Vendor Red Hat
Product Red Hat build of Apache Camel 4 for Quarkus 3
Versions Default: affected
Vendor Red Hat
Product Red Hat build of Apache Camel for Spring Boot 4
Versions Default: affected
Vendor Red Hat
Product Red Hat build of Apicurio Registry 3
Versions Default: affected
Vendor Red Hat
Product Red Hat build of Debezium 3
Versions Default: affected
Vendor Red Hat
Product Red Hat Build of Keycloak
Versions Default: affected
Vendor Red Hat
Product Red Hat build of Quarkus
Versions Default: affected
Vendor Red Hat
Product Red Hat Data Grid 8
Versions Default: affected
Vendor Red Hat
Product Red Hat Fuse 7
Versions Default: unknown
Vendor Red Hat
Product Red Hat JBoss Enterprise Application Platform 7
Versions Default: unknown
Vendor Red Hat
Product Red Hat JBoss Enterprise Application Platform 8
Versions Default: affected
Vendor Red Hat
Product Red Hat Single Sign-On 7
Versions Default: affected

Workarounds

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

References

Problem Types

  • Allocation of Resources Without Limits or Throttling CWE