Netty before 4.1.138.Final Denial of Service via SpdySessionHandler

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-100655",
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-09-27T16:27:43.159Z",
    "dateReserved": "2026-09-26T02:33:07.899Z",
    "datePublished": "2026-09-26T13:23:23.988Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck",
        "dateUpdated": "2026-09-27T16:27:43.159Z"
      },
      "datePublic": "2026-09-10T00:00:00.000Z",
      "title": "Netty before 4.1.138.Final Denial of Service via SpdySessionHandler",
      "descriptions": [
        {
          "lang": "en",
          "value": "Netty (io.netty:netty-codec-http) versions up to and including 4.1.137.Final and from 4.2.0.Final through 4.2.17.Final accept an unlimited number of concurrent remote-initiated SPDY streams: SpdySessionHandler defaults localConcurrentStreams to Integer.MAX_VALUE and exposes no API to change it. A remote peer that opens a SPDY connection and sends millions of SYN_STREAM frames with FLAG_FIN=0 causes the server to allocate unbounded heap and direct memory, eventually triggering a JVM OutOfMemoryError and crashing the service. Fixed in 4.1.138.Final and 4.2.18.Final."
        }
      ],
      "affected": [
        {
          "vendor": "netty",
          "product": "netty",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "4.1.138.Final"
            },
            {
              "version": "4.1.138.Final",
              "status": "unaffected",
              "versionType": "custom"
            }
          ]
        },
        {
          "vendor": "netty",
          "product": "netty",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "4.2.0.Final",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "4.2.18.Final"
            },
            {
              "version": "4.2.18.Final",
              "status": "unaffected",
              "versionType": "custom"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "Allocation of Resources Without Limits or Throttling",
              "cweId": "CWE-770",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/netty/netty/security/advisories/GHSA-rmcw-9fcq-wjq7",
          "name": "GitHub Security Advisory (GHSA-rmcw-9fcq-wjq7)",
          "tags": [
            "vendor-advisory"
          ]
        },
        {
          "url": "https://www.vulncheck.com/advisories/netty-before-4.1.138-final-denial-of-service-via-spdysessionhandler",
          "name": "VulnCheck Advisory: Netty before 4.1.138.Final Denial of Service via SpdySessionHandler",
          "tags": [
            "third-party-advisory"
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS"
        },
        {
          "format": "CVSS",
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "attackVector": "NETWORK",
            "attackComplexity": "LOW",
            "privilegesRequired": "NONE",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH"
          }
        }
      ]
    }
  }
}