CVE-2026-34068

{
  "id": "CVE-2026-34068",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-22T21:17:08.197",
  "lastModified": "2026-10-26T22:10:00.163",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "nimiq-transaction provides the transaction primitive to be used in Nimiq's Rust implementation. Prior to version 1.3.0, the staking contract accepts `UpdateValidator` transactions that set `new_voting_key=Some(...)` while omitting `new_proof_of_knowledge`. this skips the proof-of-knowledge requirement that is needed to prevent BLS rogue-key attacks when public keys are aggregated. Because tendermint macro block justification verification aggregates validator voting keys and verifies a single aggregated BLS signature against that aggregate public key, a rogue-key voting key in the validator set can allow an attacker to forge a quorum-looking justification while only producing a single signature. While the impact is critical, the exploitability is low: The voting keys are fixed for the epoch, so the attacker would need to know the next epoch validator set (chosen through VRF), which is unlikely. The patch for this vulnerability is included as part of v1.3.0. No known workarounds are available."
    },
    {
      "lang": "es",
      "value": "nimiq-transaction proporciona la primitiva de transacción para ser utilizada en la implementación de Nimiq en Rust. Antes de la versión 1.3.0, el contrato de staking acepta transacciones ’UpdateValidator’ que establecen ’new_voting_key=Some(...)’ mientras omiten ’new_proof_of_knowledge’. Esto omite el requisito de prueba de conocimiento que es necesario para prevenir ataques de clave maliciosa BLS cuando las claves públicas son agregadas. Debido a que la verificación de justificación de macrobloques de Tendermint agrega las claves de votación de los validadores y verifica una única firma BLS agregada contra esa clave pública agregada, una clave de votación de clave maliciosa en el conjunto de validadores puede permitir a un atacante forjar una justificación que parezca un quórum mientras solo produce una única firma. Si bien el impacto es crítico, la explotabilidad es baja: Las claves de votación están fijas para la época, por lo que el atacante necesitaría conocer el conjunto de validadores de la próxima época (elegido a través de VRF), lo cual es poco probable. El parche para esta vulnerabilidad está incluido como parte de la v1.3.0. No hay soluciones alternativas conocidas disponibles."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "nimiq",
          "product": "nimiq-transaction",
          "versions": [
            {
              "version": "< 1.3.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 4.0
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-04-23T12:56:19.048672Z",
          "id": "CVE-2026-34068",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-347"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:nimiq:nimiq_proof-of-stake:*:*:*:*:*:rust:*:*",
              "versionEndExcluding": "1.3.0",
              "matchCriteriaId": "CD0CAAD1-7626-4A4A-A6F8-9DC46FE50731"
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  "references": [
    {
      "url": "https://github.com/nimiq/core-rs-albatross/commit/e7f0ab7d2115e17d6e5548ddc60f10df1a5d645f",
      "source": "[email protected]",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://github.com/nimiq/core-rs-albatross/pull/3654",
      "source": "[email protected]",
      "tags": [
        "Issue Tracking",
        "Patch"
      ]
    },
    {
      "url": "https://github.com/nimiq/core-rs-albatross/releases/tag/v1.3.0",
      "source": "[email protected]",
      "tags": [
        "Release Notes"
      ]
    },
    {
      "url": "https://github.com/nimiq/core-rs-albatross/security/advisories/GHSA-pf4j-pf3w-95f9",
      "source": "[email protected]",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ]
    }
  ]
}