CVE-2026-56846

Full vulnerability record from the local CVENow database.

Description

A flaw in Node.js HTTP/2 handling can cause HTTP/2 retained header blocks evade maxSessionMemory and enable remote memory exhaustion. This vulnerability affects Node.js **24.x** and **22.x**.

Severity

HIGH

CVSS score

7.5 (v3.0)

Vulnerability status

Awaiting Analysis

Source identifier

[email protected]

Published

2026-08-04 01:16:19.840000

Last modified

2026-10-23 23:10:00.157000

View original CVE JSON

{
  "id": "CVE-2026-56846",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-04T01:16:19.840",
  "lastModified": "2026-10-23T23:10:00.157",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw in Node.js HTTP/2 handling can cause HTTP/2 retained header blocks evade maxSessionMemory and enable remote memory exhaustion.\r\n\r\nThis vulnerability affects Node.js **24.x** and **22.x**."
    },
    {
      "lang": "es",
      "value": "Una falla en el manejo de HTTP/2 de Node.js puede causar que los bloques de encabezado HTTP/2 retenidos evadan maxSessionMemory y permitan el agotamiento remoto de memoria.\n\nEsta vulnerabilidad afecta a Node.js 24.x y 22.x."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "nodejs",
          "product": "node",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "24.18.0",
              "lessThanOrEqual": "24.18.0",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "22.23.1",
              "lessThanOrEqual": "22.23.1",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV30": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.0",
          "vectorString": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-04T14:28:25.511403Z",
          "id": "CVE-2026-56846",
          "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-400"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://nodejs.org/en/blog/vulnerability/july-2026-security-releases",
      "source": "[email protected]"
    }
  ]
}