# CVE-2026-93568: Io.netty/netty-codec-http2: io.netty/netty-codec-http3: netty: http/2 and http/3 extended connect requests are downgraded as regular connect requests

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

A flaw was found in Netty. A remote attacker could exploit this vulnerability by sending specially crafted HTTP/2 or HTTP/3 Extended CONNECT requests. Netty's HTTP-object conversion path incorrectly processes these requests as regular HTTP/1.1 CONNECT requests, leading to a loss of critical protocol and path information. This misinterpretation can allow attackers to bypass security policies, such as routing or authorization logic, in applications that rely on Netty for HTTP/2 or HTTP/3 communication, resulting in integrity loss.

## Remediation

- workaround: See https://github.com/netty/netty/security/advisories/GHSA-w6j8-x45j-w75f for fixed versions and remediation guidance. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Build of Apache Camel 3.33.3.SP2 (io.netty/netty-codec-http2): ≥ 4.1.138.Final-redhat-00001; < * (unaffected, rpm). Source: CNA: redhat
- 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: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.95% as of 2026-11-04; percentile 61.49%

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

- Weaknesses: CWE-20

## 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-2026:70257 (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-2026-93568 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2536961 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-93568; retrieved 2026-11-04; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-93568; retrieved 2026-11-04; source updated Not reported

Revision: 9535c6574f43c3afbc01e93776eb2b97ba6bde41a67bd65ac32f6f47fe593012

Canonical: https://y2.dev/cve/CVE-2026-93568

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