Io.netty/netty-codec-http: netty: denial of service via unbounded concurrent spdy streams
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.5%
exploitation probability
0.5%top 58% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Red Hat · Red Hat AMQ Broker 7Red Hat · Red Hat AMQ ClientsRed Hat · Red Hat build of Apache Camel 4 for Quarkus 3Red Hat · Red Hat build of Apache Camel for Spring Boot 4Red Hat · Red Hat build of Apicurio Registry 3Red Hat · Red Hat build of Debezium 3Red Hat · Red Hat Build of KeycloakRed Hat · Red Hat Data Grid 8Red Hat · Red Hat Fuse 7Red Hat · Red Hat JBoss Enterprise Application Platform 7Red Hat · Red Hat JBoss Enterprise Application Platform 8Red Hat · Red Hat Single Sign-On 7References
https://access.redhat.com/errata/RHSA-2026:69440https://access.redhat.com/errata/RHSA-2026:69470https://access.redhat.com/errata/RHSA-2026:70257https://access.redhat.com/security/cve/CVE-2026-93488https://bugzilla.redhat.com/show_bug.cgi?id=2536887https://github.com/netty/netty/releases/tag/netty-4.1.138.Finalhttps://github.com/netty/netty/releases/tag/netty-4.2.18.Final