# CVE-2026-93579: Io.netty/netty-codec-http2: netty: http/2 header field values are not validated by default (cr/lf/nul passthrough)

Status: published. Published: 2026-09-18. Updated: 2026-11-04.

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.

## Remediation

- 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

- Red Hat / Red Hat Build of Debezium 3.6 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Quarkus 3.27.5.SP2 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Quarkus 3.33.3.SP2 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat JBoss Enterprise Application Platform 8.1 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat AMQ Broker 7 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Apache Camel 4 for Quarkus 3 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Apache Camel for Spring Boot 4 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat build of Apicurio Registry 3 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Build of Keycloak (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Data Grid 8 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Fuse 7 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat JBoss Enterprise Application Platform 7 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat JBoss Enterprise Application Platform 8 (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat JBoss Enterprise Application Platform Expansion Pack (netty-codec-http2): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Single Sign-On 7 (netty-codec-http2): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.90% as of 2026-11-04; percentile 59.66%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-1035

## Exploit evidence

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

## References

- https://access.redhat.com/errata/RHSA-2026:69440 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:69470 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:83612 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:95221 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2026-93579 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2536970 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-93579; retrieved 2026-11-04; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-93579; retrieved 2026-11-04; source updated Not reported

Revision: 7c1d6c0452b1b151c24888c2d1754894564c4b172a8c5c2f2b70d17aa12f8100

Canonical: https://y2.dev/cve/CVE-2026-93579

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