CVE-2026-100665CWE-295

CVE-2026-100665

High · published September 26, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
20.5
In the wild
Unconfirmed
What it is

Netty versions from 4.2.11.Final before 4.2.18.Final contain an incomplete hostname verification fix in the QUIC certificate verification path when using a plain X509TrustManager. The BoringSSLCertificateVerifyCallback discards the SSLEngine for plain trust managers, preventing endpoint identification from running even when HTTPS verification is configured. Attackers on the network path can present a certificate chain for the wrong hostname that the plain trust manager accepts, bypassing hostname authentication for QUIC clients.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS v4.0
8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
EPSS
0.00291 · 20.5th percentile
Weakness
CWE-295 · Improper Certificate Validation
Published
2026-09-26T18:16Z
References (5)
https://github.com/netty/netty/commit/09e72c4fd8007277121ed48db63a124b112b96fe · [email protected]https://github.com/netty/netty/commit/994e887ed9 · [email protected]https://github.com/netty/netty/security/advisories/GHSA-mj35-3qqm-q387 · [email protected]https://www.vulncheck.com/advisories/netty-4.2.11-through-4.2.17-quic-hostname-verification-bypass · [email protected]https://github.com/netty/netty/security/advisories/GHSA-mj35-3qqm-q387 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 28 SEP 03:25Z
    EPSS moved — → 0%
    epss
  • 26 SEP 13:23Z
    Netty 4.2.11 through 4.2.17 QUIC Hostname Verification Bypass
    cvelistv5