Improper Check for Unusual or Exceptional Conditions Affecting netty package, versions *


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
0.32% (25th percentile)

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  • Snyk IDSNYK-ECHOLATEST-NETTY-19165860
  • published22 Aug 2026
  • disclosed19 Aug 2026

Introduced: 19 Aug 2026

CVE-2026-75595  (opens in a new tab)
CWE-754  (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 is an asynchronous, event-driven network application framework. Prior to 4.1.137.Fina and 4.2.17.Final, io.netty.handler.ssl.SslClientHelloHandler#decode checks the wrong offset before reading the four-byte TLS handshake header, so a ClientHello whose handshake header spans records can cause an IndexOutOfBoundsException and invoke select(ctx, null). This selects the default SslContext instead of the SNI-specific context. In deployments where per-SNI clientAuth=REQUIRE is the sole mutual TLS gate, the default SslContext uses clientAuth=NONE or clientAuth=OPTIONAL, and no application-layer certificate verification exists, an unauthenticated remote attacker can bypass the protected route's mutual TLS requirement. This issue is fixed in versions 4.1.137.Final and 4.2.17.Final.

CVSS Base Scores

version 3.1