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FKIE_CVE-2026-47077

Vulnerability from fkie_nvd - Published: 2026-05-25 15:16 - Updated: 2026-07-24 10:10
Summary
Allocation of Resources Without Limits or Throttling vulnerability in benoitc hackney allows Flooding. hackney_h3:await_response_loop/6 accumulates the HTTP/3 response body in memory without any size cap. The after Timeout clause is a per-message inactivity timer that resets on every received chunk, housekeeping message, or settings frame — it is not a wall-clock deadline. A malicious HTTP/3 server that emits one small chunk every Timeout - 1 ms with Fin = false and never sends a final frame keeps the loop alive indefinitely while the accumulation buffer grows linearly without bound, eventually exhausting the BEAM process heap and causing an out-of-memory condition. This issue affects hackney: from 2.0.0 before 4.0.1.
Impacted products
Vendor Product Version
benoitc hackney *

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://repo.hex.pm",
          "cpes": [
            "cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "hackney_h3"
          ],
          "packageName": "hackney",
          "packageURL": "pkg:hex/hackney",
          "product": "hackney",
          "programFiles": [
            "src/hackney_h3.erl"
          ],
          "programRoutines": [
            {
              "name": "hackney_h3:await_response_loop/6"
            }
          ],
          "repo": "https://github.com/benoitc/hackney",
          "vendor": "benoitc",
          "versions": [
            {
              "lessThan": "4.0.1",
              "status": "affected",
              "version": "2.0.0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://github.com",
          "cpes": [
            "cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "hackney_h3"
          ],
          "packageName": "benoitc/hackney",
          "packageURL": "pkg:github/benoitc/hackney",
          "product": "hackney",
          "programFiles": [
            "src/hackney_h3.erl"
          ],
          "programRoutines": [
            {
              "name": "hackney_h3:await_response_loop/6"
            }
          ],
          "repo": "https://github.com/benoitc/hackney",
          "vendor": "benoitc",
          "versions": [
            {
              "lessThan": "3d25f9fea26c90609de9d64366fedfe5065413bc",
              "status": "affected",
              "version": "0334af206d5099fdf510ed9eda18e34396f065ad",
              "versionType": "git"
            }
          ]
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B119C170-E9CA-4AEE-BE04-F074E70CBF82",
              "versionEndExcluding": "4.0.1",
              "versionStartIncluding": "2.0.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Allocation of Resources Without Limits or Throttling vulnerability in benoitc hackney allows Flooding. hackney_h3:await_response_loop/6 accumulates the HTTP/3 response body in memory without any size cap. The after Timeout clause is a per-message inactivity timer that resets on every received chunk, housekeeping message, or settings frame \u2014 it is not a wall-clock deadline. A malicious HTTP/3 server that emits one small chunk every Timeout - 1 ms with Fin = false and never sends a final frame keeps the loop alive indefinitely while the accumulation buffer grows linearly without bound, eventually exhausting the BEAM process heap and causing an out-of-memory condition.\n\nThis issue affects hackney: from 2.0.0 before 4.0.1."
    },
    {
      "lang": "es",
      "value": "Vulnerabilidad de asignaci\u00f3n de recursos sin l\u00edmites ni limitaci\u00f3n en benoitc hackney permite inundaci\u00f3n. hackney_h3:await_response_loop/6 acumula el cuerpo de la respuesta HTTP/3 en memoria sin ning\u00fan l\u00edmite de tama\u00f1o. La cl\u00e1usula \u0027after Timeout\u0027 es un temporizador de inactividad por mensaje que se reinicia con cada fragmento recibido, mensaje de mantenimiento o trama de configuraci\u00f3n - no es una fecha l\u00edmite de reloj de pared. Un servidor HTTP/3 malicioso que emite un peque\u00f1o fragmento cada Timeout - 1 ms con Fin = false y nunca env\u00eda una trama final mantiene el bucle vivo indefinidamente mientras el b\u00fafer de acumulaci\u00f3n crece linealmente sin l\u00edmite, agotando eventualmente el heap del proceso BEAM y causando una condici\u00f3n de falta de memoria.\n\nEste problema afecta a hackney: desde 2.0.0 antes de 4.0.1."
    }
  ],
  "id": "CVE-2026-47077",
  "lastModified": "2026-07-24T10:10:00.197",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-47077",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-26T15:47:51.427632Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-25T15:16:22.837",
  "references": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://cna.erlef.org/cves/CVE-2026-47077.html"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/benoitc/hackney/commit/3d25f9fea26c90609de9d64366fedfe5065413bc"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "tags": [
        "Exploit",
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://github.com/benoitc/hackney/security/advisories/GHSA-jq4m-q6p2-8gwc"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-47077"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Patch",
        "Vendor Advisory"
      ],
      "url": "https://github.com/benoitc/hackney/security/advisories/GHSA-jq4m-q6p2-8gwc"
    }
  ],
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "type": "Secondary"
    }
  ]
}



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