CVE-2026-59644

{
  "id": "CVE-2026-59644",
  "sourceIdentifier": "91579145-5d7b-4cc5-b925-a0262ff19630",
  "published": "2026-08-03T01:16:44.467",
  "lastModified": "2026-10-23T22:10:00.160",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In Bouncy Castle for Java before 1.85, MLS hash-ratchet honours arbitrary 32-bit generation counter from sender."
    },
    {
      "lang": "es",
      "value": "En Bouncy Castle para Java antes de 1.85, el hash-ratchet de MLS respeta el contador de generación arbitrario de 32 bits del remitente."
    }
  ],
  "affected": [
    {
      "source": "91579145-5d7b-4cc5-b925-a0262ff19630",
      "affectedData": [
        {
          "vendor": "Legion of the Bouncy Castle Inc.",
          "product": "BC-JAVA",
          "defaultStatus": "unaffected",
          "collectionURL": "https://www.bouncycastle.org/download/bouncy-castle-java/",
          "packageName": "bcmls",
          "modules": [
            "mls"
          ],
          "platforms": [
            "all"
          ],
          "programFiles": [
            "GroupKeySet"
          ],
          "repo": "https://github.com/bcgit/bc-java",
          "packageURL": "pkg:maven/org.bouncycastle/bcmls-jdk18on",
          "versions": [
            {
              "version": "1.73",
              "lessThan": "1.85",
              "versionType": "maven",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "91579145-5d7b-4cc5-b925-a0262ff19630",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/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:Amber",
          "baseScore": 8.7,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "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": "AMBER"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/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": "2026-08-03T13:36:00.578531Z",
          "id": "CVE-2026-59644",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "91579145-5d7b-4cc5-b925-a0262ff19630",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-834"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "1.85",
              "matchCriteriaId": "FA6A5663-2E62-44AA-8A64-A3CB0DC8813B"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/bcgit/bc-java/commit/610d8757d855afe197df0de6d831cb75c81e3b9f",
      "source": "91579145-5d7b-4cc5-b925-a0262ff19630",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059644",
      "source": "91579145-5d7b-4cc5-b925-a0262ff19630",
      "tags": [
        "Third Party Advisory"
      ]
    }
  ]
}