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CVE-2026-116542

Full vulnerability record from the local CVENow database.

Description

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
MEDIUM
CVSS score
6.9 (v4.0)
Vulnerability status
Awaiting Analysis
Source identifier
Published
2026-10-26 16:17:19.680000
Last modified
2026-10-26 16:54:08.707000
View original CVE JSON
{
  "id": "CVE-2026-116542",
  "sourceIdentifier": "[email protected]",
  "published": "2026-10-26T16:17:19.680",
  "lastModified": "2026-10-26T16:54:08.707",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "netty",
          "product": "netty-tcnative",
          "defaultStatus": "unaffected",
          "collectionURL": "https://repo1.maven.org/maven2/io/netty/netty-tcnative/",
          "packageName": "io.netty:netty-tcnative",
          "repo": "https://github.com/netty/netty-tcnative",
          "packageURL": "pkg:maven/io.netty/netty-tcnative",
          "versions": [
            {
              "version": "0",
              "lessThan": "2.0.84.Final",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "netty",
          "product": "netty-tcnative-boringssl-static",
          "defaultStatus": "unaffected",
          "collectionURL": "https://repo1.maven.org/maven2/io/netty/netty-tcnative-boringssl-static/",
          "packageName": "io.netty:netty-tcnative-boringssl-static",
          "repo": "https://github.com/netty/netty-tcnative",
          "packageURL": "pkg:maven/io.netty/netty-tcnative-boringssl-static",
          "versions": [
            {
              "version": "0",
              "lessThan": "2.0.84.Final",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 6.9,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "LOW",
          "vulnAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-176"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/netty/netty-tcnative",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/netty/netty-tcnative/blob/netty-tcnative-parent-2.0.83.Final/openssl-dynamic/src/main/c/sslcontext.c#L2608",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/netty/netty-tcnative/commit/a879c85b9776cf478aada3ca69e60b8c0a99ed38",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/netty/netty-tcnative/releases/tag/netty-tcnative-parent-2.0.84.Final",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/netty/netty-tcnative/security/advisories/GHSA-2784-hxmm-4hgf",
      "source": "[email protected]"
    },
    {
      "url": "https://www.vulncheck.com/advisories/netty-netty-tcnative-before-2.0.84-final-sni-hostname-spoofing-via-modified-utf-8-decoding",
      "source": "[email protected]"
    }
  ]
}