Input validation error in Jetty - CVE-2026-6790
Published: July 13, 2026
Vulnerability identifier: #VU137399
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-6790
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass host-based access controls and interfere with hostname-based security decisions.
The vulnerability exists due to improper input validation in HTTP/2 and HTTP/3 server-side request handling when processing requests with mismatched :authority and Host values. A remote attacker can send a specially crafted request containing conflicting host identities to bypass host-based access controls and interfere with hostname-based security decisions.
Different layers may interpret different host values from the same request, which can affect virtual host isolation, multi-tenant routing, redirect or callback URL construction, proxy trust chains, and logging.
Affected software
Jetty
How to mitigate CVE-2026-6790
Install security update from vendor's website.
Jetty - addressed in versions 9.4.61, 10.0.29, 11.0.29, 12.0.35, 12.1.9