CVE-2026-116542

Netty netty-tcnative before 2.0.84.Final contains an SNI hostname spoofing vulnerability that allows remote unauthenticated clients to alter hostnames via JNI NewStringUTF decoding. Attackers can send overlong encodings like 0xC0 0x80 in the ClientHello server_name to confuse SNI-based certificate selection, access decisions, and logging.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty-tcnative
https://github.com/netty/netty-tcnative/blob/netty-tcnative-parent-2.0.83.Final/openssl-dynamic/src/main/c/sslcontext.c#L2608
https://github.com/netty/netty-tcnative/commit/a879c85b9776cf478aada3ca69e60b8c0a99ed38
https://github.com/netty/netty-tcnative/releases/tag/netty-tcnative-parent-2.0.84.Final
https://github.com/netty/netty-tcnative/security/advisories/GHSA-2784-hxmm-4hgf
https://www.vulncheck.com/advisories/netty-netty-tcnative-before-2.0.84-final-sni-hostname-spoofing-via-modified-utf-8-decoding
https://github.com/netty/netty-tcnative/security/advisories/GHSA-2784-hxmm-4hgf

Configurations

No configuration.

History

31 Oct 2026, 02:17

Type	Values Removed	Values Added
References	~~() https://github.com/netty/netty-tcnative/security/advisories/GHSA-2784-hxmm-4hgf -~~	() https://github.com/netty/netty-tcnative/security/advisories/GHSA-2784-hxmm-4hgf -

26 Oct 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-26 16:17

Updated : 2026-10-31 02:17

NVD link : CVE-2026-116542

Mitre link : CVE-2026-116542

CVE.ORG link : CVE-2026-116542

JSON object : View

Products Affected

No product.

CWE

CWE-176

Improper Handling of Unicode Encoding

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