CVE-2026-93569
Medium
Elevated severity or exploit probability.
CVSS base
8.2
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
EPSS — probability of exploitation (30 days)
0.7%
51.1th percentile
CISA KEV
Not listed
Weakness / dates
CWE-444
Published 2026-09-18 · modified 2026-09-22
Description
A flaw was found in Netty. A remote unauthenticated attacker can exploit a vulnerability in Netty's HTTP/1 to HTTP/2 conversion process. When an HTTP/1 request includes both an absolute-form request-target and a conflicting Host header, Netty incorrectly prioritizes the Host header for the HTTP/2 :authority field, discarding the original request-target authority. This inconsistency can allow an attacker to bypass security controls in Netty-based proxies or gateways, potentially leading to unauthorized access, cache poisoning, or misrouting of requests.