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GHSA-4MP9-239F-G9HG

Vulnerability from github – Published: 2026-07-22 21:48 – Updated: 2026-07-22 21:48
VLAI
Summary
Netty: WebSockets V07/V08 handshaker missing Connection/Upgrade validation
Details

Summary

An attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending Sec-WebSocket-Version: 7 and omitting Connection: Upgrade / Upgrade: websocket headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks.

Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Show details on source website
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 4.2.15.Final"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "io.netty:netty-codec-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.2.0.Final"
            },
            {
              "fixed": "4.2.16.Final"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "io.netty:netty-codec-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.1.136.Final"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-59898"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-22T21:48:59Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "## Summary\nAn attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` / `Upgrade: websocket` headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks.",
  "id": "GHSA-4mp9-239f-g9hg",
  "modified": "2026-07-22T21:48:59Z",
  "published": "2026-07-22T21:48:59Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/netty/netty/security/advisories/GHSA-4mp9-239f-g9hg"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/netty/netty"
    },
    {
      "type": "WEB",
      "url": "https://github.com/netty/netty/releases/tag/netty-4.1.136.Final"
    },
    {
      "type": "WEB",
      "url": "https://github.com/netty/netty/releases/tag/netty-4.2.16.Final"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Netty: WebSockets V07/V08 handshaker missing Connection/Upgrade validation"
}



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