Io.netty/netty-codec-http: netty: denial of service via unbounded concurrent spdy streams
Summary
| CVE | CVE-2026-93488 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-18 12:17:30 UTC |
| Updated | 2026-09-22 23:17:07 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.005060000 probability, percentile 0.422700000 (date 2026-09-23)
Problem Types: CWE-770 | CWE-770 Allocation of Resources Without Limits or Throttling
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat AMQ Broker 7 | Not specified | Not specified |
| CNA | Red Hat | Red Hat AMQ Clients | Not specified | Not specified |
| CNA | Red Hat | Red Hat Build Of Apache Camel 4 For Quarkus 3 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Build Of Apache Camel For Spring Boot 4 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Build Of Apicurio Registry 3 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Build Of Debezium 3 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Build Of Keycloak | Not specified | Not specified |
| CNA | Red Hat | Red Hat Data Grid 8 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Fuse 7 | Not specified | Not specified |
| CNA | Red Hat | Red Hat JBoss Enterprise Application Platform 7 | Not specified | Not specified |
| CNA | Red Hat | Red Hat JBoss Enterprise Application Platform 8 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Single Sign-On 7 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/errata/RHSA-2026:69470 | [email protected] | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-93488 | [email protected] | access.redhat.com | |
| github.com/netty/netty/releases/tag/netty-4.1.138.Final | [email protected] | github.com | |
| access.redhat.com/errata/RHSA-2026:70257 | [email protected] | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:69440 | [email protected] | access.redhat.com | |
| github.com/netty/netty/releases/tag/netty-4.2.18.Final | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-09-10T00:39:48.000Z | Reported to Red Hat. |
| CNA | 2026-09-10T00:39:48.000Z | Made public. |
Workarounds
CNA: 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.
There are currently no legacy QID mappings associated with this CVE.