CVE-2026-93492

Full vulnerability record from the local CVENow database.
Description

A flaw was found in Netty's HTTP/2 HpackEncoder. A remote attacker can exploit this by sending HTTP/2 SETTINGS frames with a very large MAX_HEADER_TABLE_SIZE. This causes the HpackEncoder to store an excessive number of unique headers, leading to increased CPU usage and memory consumption, ultimately resulting in a Denial of Service (DoS).
Severity
MEDIUM
CVSS score
5.3 (v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
[email protected]
Published
2026-09-18 13:18:38.877000
Last modified
2026-11-04 15:17:56.060000
View original CVE JSON
{
  "id": "CVE-2026-93492",
  "sourceIdentifier": "[email protected]",
  "published": "2026-09-18T13:18:38.877",
  "lastModified": "2026-11-04T15:17:56.060",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in Netty's HTTP/2 HpackEncoder. A remote attacker can exploit this by sending HTTP/2 SETTINGS frames with a very large MAX_HEADER_TABLE_SIZE. This causes the HpackEncoder to store an excessive number of unique headers, leading to increased CPU usage and memory consumption, ultimately resulting in a Denial of Service (DoS)."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Red Hat",
          "product": "Red Hat Build of Debezium 3.6",
          "defaultStatus": "unaffected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "netty-codec-http2",
          "cpes": [
            "cpe:/a:redhat:debezium:3.6"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat build of Quarkus 3.27.5.SP2",
          "defaultStatus": "unaffected",
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "packageName": "netty-codec-http2",
          "cpes": [
            "cpe:/a:redhat:quarkus:3.27::el8"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat build of Quarkus 3.33.3.SP2",
          "defaultStatus": "unaffected",
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "packageName": "netty-codec-http2",
          "cpes": [
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          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat JBoss Enterprise Application Platform 8.1",
          "defaultStatus": "unaffected",
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          "packageName": "netty-codec-http2",
          "cpes": [
            "cpe:/a:redhat:jboss_enterprise_application_platform_xp:6.0"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat AMQ Broker 7",
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          "packageName": "netty-codec-http2",
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        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat build of Apache Camel 4 for Quarkus 3",
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          "packageName": "netty-codec-http2",
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          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat build of Apicurio Registry 3",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "netty-codec-http2",
          "cpes": [
            "cpe:/a:redhat:apicurio_registry:3"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Build of Keycloak",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "netty-codec-http2",
          "cpes": [
            "cpe:/a:redhat:build_keycloak:"
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        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Data Grid 8",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "netty-codec-http2",
          "cpes": [
            "cpe:/a:redhat:jboss_data_grid:8"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Fuse 7",
          "defaultStatus": "unknown",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "netty-codec-http2",
          "cpes": [
            "cpe:/a:redhat:jboss_fuse:7"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat JBoss Enterprise Application Platform 7",
          "defaultStatus": "unknown",
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "packageName": "netty-codec-http2",
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          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat JBoss Enterprise Application Platform 8",
          "defaultStatus": "unaffected",
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "packageName": "netty-codec-http2",
          "cpes": [
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          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat JBoss Enterprise Application Platform Expansion Pack",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "packageName": "netty-codec-http2",
          "cpes": [
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          ]
        },
        {
          "vendor": "Red Hat",
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          "defaultStatus": "unknown",
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          "packageName": "netty-codec-http2",
          "cpes": [
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          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "LOW"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-09-18T14:40:19.700669Z",
          "id": "CVE-2026-93492",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-1035"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:69440",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:69470",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:83612",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:95221",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/security/cve/CVE-2026-93492",
      "source": "[email protected]"
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2536895",
      "source": "[email protected]"
    }
  ]
}