Improper Validation of Certificate with Host Mismatch Affecting netty package, versions *


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.16% (5th percentile)

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  • Snyk IDSNYK-ECHOLATEST-NETTY-19233517
  • published23 Aug 2026
  • disclosed22 Aug 2026

Introduced: 22 Aug 2026

CVE-2026-62243  (opens in a new tab)
CWE-297  (opens in a new tab)

How to fix?

There is no fixed version for Echo:latest netty.

NVD Description

Note: Versions mentioned in the description apply only to the upstream netty package and not the netty package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

Netty (io.netty:netty-handler) versions from 4.2.0.Final through 4.2.16.Final and versions through 4.1.136.Final disable TLS hostname verification on the SslProvider.OPENSSL client path when a plain (non-extended) X509TrustManager is used and Unsafe-based trust-manager wrapping is unavailable (Java 25+). In this configuration the OpenSSL client does not perform hostname verification, allowing a man-in-the-middle attacker to present a certificate issued for a different hostname that is accepted without validation. Fixed in 4.2.17.Final and 4.1.137.Final.

CVSS Base Scores

version 3.1