CVE-2026-62243
Netty 4.2.0 through 4.2.16 TLS Hostname Verification Bypass
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-297 |
| Vendor | netty |
| Product | netty |
| Published | Aug 22, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
netty / netty
4.2.0.Final < 4.2.16.Final
netty / netty
0 < 4.1.137.Final
References
Credits
🔍 violetagg