CVE-2026-116542 (GCVE-0-2026-116542)

Vulnerability from cvelistv5 – Published: 2026-10-26 14:59 – Updated: 2026-10-26 14:59
VLAI
Title
Netty netty-tcnative before 2.0.84.Final SNI Hostname Spoofing via Modified UTF-8 Decoding
Summary
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.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-176 - Improper Handling of Unicode Encoding
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6843 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
netty netty-tcnative Affected: 0 , < 2.0.84.Final (custom)
guessed Create a notification for this product.
netty netty-tcnative-boringssl-static Affected: 0 , < 2.0.84.Final (custom)
guessed Create a notification for this product.
Date Public
2026-08-07 00:00
Credits
Yu Bao, PayPal Cyber Security Team
Show details on NVD website
To clipboard 

{
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          "packageName": "io.netty:netty-tcnative",
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      "credits": [
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          "value": "Yu Bao, PayPal Cyber Security Team"
        }
      ],
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      "descriptions": [
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        }
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          "url": "https://github.com/netty/netty-tcnative/security/advisories/GHSA-2784-hxmm-4hgf"
        },
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          "url": "https://github.com/netty/netty-tcnative/blob/netty-tcnative-parent-2.0.83.Final/openssl-dynamic/src/main/c/sslcontext.c#L2608"
        },
        {
          "name": "netty-tcnative netty-tcnative-parent-2.0.84.Final Release Notes",
          "tags": [
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          "url": "https://github.com/netty/netty-tcnative/releases/tag/netty-tcnative-parent-2.0.84.Final"
        },
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          "tags": [
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          "url": "https://github.com/netty/netty-tcnative"
        },
        {
          "name": "VulnCheck Advisory: Netty netty-tcnative before 2.0.84.Final SNI Hostname Spoofing via Modified UTF-8 Decoding",
          "tags": [
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        }
      ],
      "title": "Netty netty-tcnative before 2.0.84.Final SNI Hostname Spoofing via Modified UTF-8 Decoding",
      "x_generator": {
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      }
    }
  },
  "cveMetadata": {
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    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-116542",
    "datePublished": "2026-10-26T14:59:41.528Z",
    "dateReserved": "2026-10-26T14:30:58.474Z",
    "dateUpdated": "2026-10-26T14:59:41.528Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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        "cveTags": [],
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          }
        ],
        "id": "CVE-2026-116542",
        "lastModified": "2026-10-26T16:54:08.707",
        "metrics": {
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                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
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                "modifiedAttackRequirements": "NOT_DEFINED",
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                "modifiedPrivilegesRequired": "NOT_DEFINED",
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                "providerUrgency": "NOT_DEFINED",
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  }
}



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