7.5High
CVE-2026-93567Io.netty/netty-codec-http2: http/1 authority-form connect is translated to malformed http/2 connect with host-controlled :authority
Description
A flaw was found in Netty's HTTP/2 codec. When converting HTTP/1 CONNECT requests to HTTP/2, the component incorrectly uses the Host header instead of the CONNECT authority-form request-target for the tunnel authority. A remote attacker can exploit this by supplying a different Host header, leading to a malformed HTTP/2 CONNECT request. This can bypass security controls such as tunnel allow-lists or egress policies, resulting in integrity loss.
Weakness (CWE):
CWE-20
Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.
Affected products and versions
References and patches
- RHSA-2026:69440 vendor-advisory
- RHSA-2026:69470 vendor-advisory
- RHSA-2026:70257 vendor-advisory
- RHSA-2026:83612 vendor-advisory
- RHSA-2026:95221 vendor-advisory
- RHSA-2026:95759 vendor-advisory
- RHSA-2026:95760 vendor-advisory
- RHSA-2026:95761 vendor-advisory
- RHSA-2026:95762 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-93567 vdb-entry
- RHBZ#2536955 issue-tracking