CVE-2026-93579

Io.netty/netty-codec-http2: netty: http/2 header field values are not validated by default (cr/lf/nul passthrough)

publishedCWE-1035

A flaw was found in Netty's HTTP/2 stack. This vulnerability allows a remote attacker to inject prohibited characters, such as NUL, Line Feed, and Carriage Return, into HTTP/2 header field values due to insufficient validation. When these values cross an HTTP/2 to HTTP/1.1 translation boundary, they can be exploited for request smuggling, header injection, or response splitting. This could lead to unauthorized access, data manipulation, or other security bypasses.

Technical severity6.5 mediumCVSS 3.1 · CNA: redhat

Published2026-09-18Source updated 2026-11-04

Collected2026-11-042 attributed sources

Fixes and workarounds

Workaround

See https://github.com/netty/netty/security/advisories/GHSA-8whp-c7w8-2m72 for fixed versions and remediation guidance.

Source: CNA: redhat

Affected products and versions

Affected products, source version ranges and reporting authorities
Product	Versions	Authority
Red Hat Build of Debezium 3.6 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat build of Quarkus 3.27.5.SP2 Red Hat `netty-codec-http2` https://access.redhat.com/jbossnetwork/restricted/listSoftware.html	Range not reported Other versions: unaffected	CNA: redhat
Red Hat build of Quarkus 3.33.3.SP2 Red Hat `netty-codec-http2` https://access.redhat.com/jbossnetwork/restricted/listSoftware.html	Range not reported Other versions: unaffected	CNA: redhat
Red Hat JBoss Enterprise Application Platform 8.1 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat AMQ Broker 7 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unaffected	CNA: redhat
Red Hat build of Apache Camel 4 for Quarkus 3 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat build of Apache Camel for Spring Boot 4 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat build of Apicurio Registry 3 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat Build of Keycloak Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat Data Grid 8 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: affected	CNA: redhat
Red Hat Fuse 7 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat
Red Hat JBoss Enterprise Application Platform 7 Red Hat `netty-codec-http2` https://access.redhat.com/jbossnetwork/restricted/listSoftware.html	Range not reported Other versions: unknown	CNA: redhat
Red Hat JBoss Enterprise Application Platform 8 Red Hat `netty-codec-http2` https://access.redhat.com/jbossnetwork/restricted/listSoftware.html	Range not reported Other versions: unaffected	CNA: redhat
Red Hat JBoss Enterprise Application Platform Expansion Pack Red Hat `netty-codec-http2` https://access.redhat.com/jbossnetwork/restricted/listSoftware.html	Range not reported Other versions: affected	CNA: redhat
Red Hat Single Sign-On 7 Red Hat `netty-codec-http2` https://access.redhat.com/downloads/content/package-browser/	Range not reported Other versions: unknown	CNA: redhat

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / score	Vector	Authority
3.1 / 6.5 medium	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N`	CNA: redhat

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

https://access.redhat.com/errata/RHSA-2026:69440CNA: redhat · vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:69470CNA: redhat · vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:83612CNA: redhat · vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:95221CNA: redhat · vendor-advisory, x_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-93579CNA: redhat · vdb-entry, x_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2536970CNA: redhat · issue-tracking, x_refsource_REDHAT

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