CVE-2026-71397

{
  "id": "CVE-2026-71397",
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "published": "2026-11-06T21:17:10.480",
  "lastModified": "2026-11-06T21:17:10.480",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Allocation of Resources Without Limits or Throttling vulnerability in elixir-grpc grpc_server allows unauthenticated attackers to exhaust memory and crash the node via an oversized client-streaming or bidirectional-streaming request body.\n\nThe streaming read clause of 'Elixir.GRPC.Server.Adapters.Cowboy.Handler':info/3 (grpc_server/lib/grpc/server/adapters/cowboy/handler.ex) never checks the configured max_body_size. Only the unary read path enforces that cap. 'Elixir.GRPC.Server.Adapters.Cowboy':reading_stream/1 (grpc_server/lib/grpc/server/adapters/cowboy.ex) appends every received chunk to its buffer until a complete length-prefixed message arrives. A client can declare a very large message and send it across many small HTTP/2 DATA frames, and the server buffers all of it.\n\nThis issue affects grpc_server: from 1.0.0 before 1.0.6."
    }
  ],
  "affected": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "affectedData": [
        {
          "vendor": "elixir-grpc",
          "product": "grpc_server",
          "defaultStatus": "unaffected",
          "collectionURL": "https://repo.hex.pm",
          "packageName": "grpc_server",
          "cpes": [
            "cpe:2.3:a:elixir-grpc:grpc_server:*:*:*:*:*:*:*:*"
          ],
          "modules": [
            "'Elixir.GRPC.Server.Adapters.Cowboy.Handler'",
            "'Elixir.GRPC.Server.Adapters.Cowboy'"
          ],
          "programFiles": [
            "lib/grpc/server/adapters/cowboy/handler.ex",
            "lib/grpc/server/adapters/cowboy.ex"
          ],
          "programRoutines": [
            {
              "name": "'Elixir.GRPC.Server.Adapters.Cowboy.Handler':info/3"
            },
            {
              "name": "'Elixir.GRPC.Server.Adapters.Cowboy':reading_stream/1"
            }
          ],
          "repo": "https://github.com/elixir-grpc/grpc",
          "packageURL": "pkg:hex/grpc_server",
          "versions": [
            {
              "version": "1.0.0",
              "lessThan": "1.0.6",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "elixir-grpc",
          "product": "grpc_server",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com",
          "packageName": "elixir-grpc/grpc",
          "cpes": [
            "cpe:2.3:a:elixir-grpc:grpc_server:*:*:*:*:*:*:*:*"
          ],
          "modules": [
            "'Elixir.GRPC.Server.Adapters.Cowboy.Handler'",
            "'Elixir.GRPC.Server.Adapters.Cowboy'"
          ],
          "programFiles": [
            "grpc_server/lib/grpc/server/adapters/cowboy/handler.ex",
            "grpc_server/lib/grpc/server/adapters/cowboy.ex"
          ],
          "programRoutines": [
            {
              "name": "'Elixir.GRPC.Server.Adapters.Cowboy.Handler':info/3"
            },
            {
              "name": "'Elixir.GRPC.Server.Adapters.Cowboy':reading_stream/1"
            }
          ],
          "repo": "https://github.com/elixir-grpc/grpc",
          "packageURL": "pkg:github/elixir-grpc/grpc",
          "versions": [
            {
              "version": "49e18c3ec6bb9afe2f712caad3dbab5c56a68a00",
              "lessThan": "0b663ca53dbf0f36f7f67ff1d0026f4482a18915",
              "versionType": "git",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "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",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://cna.erlef.org/cves/CVE-2026-71397.html",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://github.com/elixir-grpc/grpc/commit/0b663ca53dbf0f36f7f67ff1d0026f4482a18915",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://github.com/elixir-grpc/grpc/commit/49e18c3ec6bb9afe2f712caad3dbab5c56a68a00",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://github.com/elixir-grpc/grpc/security/advisories/GHSA-vx6q-cr5q-945g",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-71397",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    }
  ]
}