CVE-2026-93573Io.netty/netty-codec-http: netty split transfer-encoding fields bypass final-chunked validation and enable request smuggling

Description

A flaw was found in Netty's HTTP/1.1 decoder. This vulnerability allows a remote attacker to bypass `Transfer-Encoding` header validation by splitting the `Transfer-Encoding` field across multiple headers, with the last field containing a non-final transfer coding like `gzip` or `deflate`. This bypass can lead to HTTP request smuggling, enabling attackers to bypass security controls, desynchronize request processing, or cause requests to be processed in an unintended context.

Timeline

Scores

EPSS (exploitation in 30 days)

1.1% · top 34% of all CVEs (14 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: yes · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.

Affected products

• Red Hat · Red Hat Build of Debezium 3.6

  All versions: unaffected

• Red Hat · Red Hat build of Keycloak 26.4

  • unaffected 26.4.17-2 – < *

• Red Hat · Red Hat build of Keycloak 26.4

  • unaffected 26.4-29 – < *

• Red Hat · Red Hat build of Keycloak 26.4

  • unaffected 26.4-30 – < *

• Red Hat · Red Hat build of Keycloak 26.4.17

  All versions: unaffected

• Red Hat · Red Hat build of Keycloak 26.6

  • unaffected 26.6.8-2 – < *

• Red Hat · Red Hat build of Keycloak 26.6

  • unaffected 26.6-24 – < *

• Red Hat · Red Hat build of Keycloak 26.6

  • unaffected 26.6-24 – < *

• Red Hat · Red Hat build of Keycloak 26.6.8

  All versions: unaffected

• Red Hat · Red Hat build of Quarkus 3.27.5.SP2

  All versions: unaffected

• Red Hat · Red Hat build of Quarkus 3.33.3.SP2

  All versions: unaffected

• Red Hat · Red Hat JBoss Enterprise Application Platform 8.1

  All versions: unaffected

• Red Hat · Red Hat AMQ Broker 7

  All versions: affected

• Red Hat · Red Hat AMQ Clients

  All versions: affected

• Red Hat · Red Hat build of Apache Camel 4 for Quarkus 3

  All versions: affected

• Red Hat · Red Hat build of Apache Camel for Spring Boot 4

  All versions: affected

• Red Hat · Red Hat build of Apicurio Registry 3

  All versions: affected

• Red Hat · Red Hat Data Grid 8

  All versions: affected

• Red Hat · Red Hat Fuse 7

  All versions: unknown

• Red Hat · Red Hat JBoss Enterprise Application Platform 7

  All versions: unknown

• Red Hat · Red Hat Single Sign-On 7

  All versions: unknown

What to do

Workaround: See https://github.com/netty/netty/security/advisories/GHSA-3jrc-fchc-59pw for fixed versions and remediation guidance.

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• EUVD EUVD-2026-82979 (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-93573](https://cveledger.app/badge/CVE-2026-93573.svg)](https://cveledger.app/cve/CVE-2026-93573)

Record last updated 6 Nov 2026, 17:27 UTC.