CVE-2026-65631

Full vulnerability record from the local CVENow database.

Description

Inefficient Algorithmic Complexity in erlang-jose allows an unauthenticated remote attacker to cause a CPU-exhaustion denial of service by submitting a crafted RSA JSON Web Key. When an application parses an untrusted JWK through the public jose_jwk:from_binary/1 or jose_jwk:from_map/1 API (or the Elixir wrappers JOSE.JWK.from_binary/1 and JOSE.JWK.from_map/1), an RSA private key that supplies d, e, and n but omits all Chinese Remainder Theorem parameters (p, q, dp, dq, qi) is routed into convert_sfm_to_crt/1, which tries to recover the missing primes by factoring the modulus. The three integers are read straight from the base64url input and are never validated as a real RSA key. When the modulus cannot be split into two factors (for example, when it is itself prime), the search loop convert_sfm_to_crt_find_p/6 performs a modular exponentiation over the attacker-sized modulus on every iteration and never succeeds. A single request of a few hundred bytes forces close to one CPU-second of work before an internal one-second watchdog kills the worker, and a larger modulus raises the cost further. By flooding such requests an attacker can saturate every scheduler and deny service, without credentials, a valid RSA key, or any special configuration. This issue affects jose: from 1.7.7 before 1.11.13.

Severity

MEDIUM

CVSS score

6.9 (v4.0)

Vulnerability status

Received

Source identifier

6b3ad84c-e1a6-4bf7-a703-f496b71e49db

Published

2026-10-26 20:17:58.997000

Last modified

2026-10-26 20:17:58.997000

View original CVE JSON

{
  "id": "CVE-2026-65631",
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "published": "2026-10-26T20:17:58.997",
  "lastModified": "2026-10-26T20:17:58.997",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Inefficient Algorithmic Complexity in erlang-jose allows an unauthenticated remote attacker to cause a CPU-exhaustion denial of service by submitting a crafted RSA JSON Web Key.\n\nWhen an application parses an untrusted JWK through the public jose_jwk:from_binary/1 or jose_jwk:from_map/1 API (or the Elixir wrappers JOSE.JWK.from_binary/1 and JOSE.JWK.from_map/1), an RSA private key that supplies d, e, and n but omits all Chinese Remainder Theorem parameters (p, q, dp, dq, qi) is routed into convert_sfm_to_crt/1, which tries to recover the missing primes by factoring the modulus. The three integers are read straight from the base64url input and are never validated as a real RSA key. When the modulus cannot be split into two factors (for example, when it is itself prime), the search loop convert_sfm_to_crt_find_p/6 performs a modular exponentiation over the attacker-sized modulus on every iteration and never succeeds. A single request of a few hundred bytes forces close to one CPU-second of work before an internal one-second watchdog kills the worker, and a larger modulus raises the cost further. By flooding such requests an attacker can saturate every scheduler and deny service, without credentials, a valid RSA key, or any special configuration.\n\nThis issue affects jose: from 1.7.7 before 1.11.13."
    }
  ],
  "affected": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "affectedData": [
        {
          "vendor": "potatosalad",
          "product": "jose",
          "defaultStatus": "unaffected",
          "collectionURL": "https://repo.hex.pm",
          "packageName": "jose",
          "cpes": [
            "cpe:2.3:a:potatosalad:jose:*:*:*:*:*:*:*:*"
          ],
          "modules": [
            "jose_jwk_kty_rsa",
            "jose_jwk",
            "'Elixir.JOSE.JWK'"
          ],
          "programFiles": [
            "src/jwk/jose_jwk_kty_rsa.erl",
            "src/jwk/jose_jwk.erl",
            "lib/jose/jwk.ex"
          ],
          "programRoutines": [
            {
              "name": "jose_jwk_kty_rsa:from_map/1"
            },
            {
              "name": "jose_jwk_kty_rsa:convert_sfm_to_crt/1"
            },
            {
              "name": "jose_jwk_kty_rsa:convert_sfm_to_crt_find_p/6"
            },
            {
              "name": "jose_jwk:from_binary/1"
            },
            {
              "name": "jose_jwk:from_map/1"
            },
            {
              "name": "'Elixir.JOSE.JWK':from_binary/1"
            },
            {
              "name": "'Elixir.JOSE.JWK':from_map/1"
            }
          ],
          "repo": "https://github.com/potatosalad/erlang-jose",
          "packageURL": "pkg:hex/jose",
          "versions": [
            {
              "version": "1.7.7",
              "lessThan": "1.11.13",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "potatosalad",
          "product": "jose",
          "defaultStatus": "unaffected",
          "collectionURL": "https://github.com",
          "packageName": "potatosalad/erlang-jose",
          "cpes": [
            "cpe:2.3:a:potatosalad:jose:*:*:*:*:*:*:*:*"
          ],
          "modules": [
            "jose_jwk_kty_rsa",
            "jose_jwk",
            "'Elixir.JOSE.JWK'"
          ],
          "programFiles": [
            "src/jwk/jose_jwk_kty_rsa.erl",
            "src/jwk/jose_jwk.erl",
            "lib/jose/jwk.ex"
          ],
          "programRoutines": [
            {
              "name": "jose_jwk_kty_rsa:from_map/1"
            },
            {
              "name": "jose_jwk_kty_rsa:convert_sfm_to_crt/1"
            },
            {
              "name": "jose_jwk_kty_rsa:convert_sfm_to_crt_find_p/6"
            },
            {
              "name": "jose_jwk:from_binary/1"
            },
            {
              "name": "jose_jwk:from_map/1"
            },
            {
              "name": "'Elixir.JOSE.JWK':from_binary/1"
            },
            {
              "name": "'Elixir.JOSE.JWK':from_map/1"
            }
          ],
          "repo": "https://github.com/potatosalad/erlang-jose",
          "packageURL": "pkg:github/potatosalad/erlang-jose",
          "versions": [
            {
              "version": "d19e1ba68d88c68d29aa942be2573a22dbafca1f",
              "lessThan": "bfd336c0062bff93e65d08c22361897e96afd956",
              "versionType": "git",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/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": 6.9,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "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-407"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://cna.erlef.org/cves/CVE-2026-65631.html",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://github.com/potatosalad/erlang-jose/commit/bfd336c0062bff93e65d08c22361897e96afd956",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://github.com/potatosalad/erlang-jose/commit/d19e1ba68d88c68d29aa942be2573a22dbafca1f",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://github.com/potatosalad/erlang-jose/security/advisories/GHSA-3m45-vrpj-xmrq",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    },
    {
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-65631",
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    }
  ]
}