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CVE-2021-42072

Status: ModifiedHigh (8.8)—

An issue was discovered in Barrier before 2.4.0. The barriers component (aka the server-side implementation of Barrier) does not sufficiently verify the identify of connecting clients. Clients can thus exploit weaknesses in the provided protocol to cause denial-of-service or stage further attacks that could lead to information leaks or integrity corruption.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (2)

Barrier Project — BarrierFedoraproject — Fedora

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2021-42072",
  "cveTags": [],
  "metrics": {
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          "baseScore": 6.5,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:S/C:P/I:P/A:P",
          "authentication": "SINGLE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
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        "acInsufInfo": false,
        "impactScore": 6.4,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 8,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
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          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
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          "userInteraction": "NONE",
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  "published": "2021-11-08T04:15:08.437",
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
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          "value": "CWE-287"
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      ]
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  ],
  "descriptions": [
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      "lang": "en",
      "value": "An issue was discovered in Barrier before 2.4.0. The barriers component (aka the server-side implementation of Barrier) does not sufficiently verify the identify of connecting clients. Clients can thus exploit weaknesses in the provided protocol to cause denial-of-service or stage further attacks that could lead to information leaks or integrity corruption."
    },
    {
      "lang": "es",
      "value": "Se ha detectado un problema en Barrier versiones anteriores a 2.4.0. El componente de barreras (también se conoce como implementación del lado del servidor de Barrier) no verifica suficientemente la identificación de los clientes que se conectan. Por lo tanto, los clientes pueden aprovechar los puntos débiles del protocolo proporcionado para causar una denegación de servicio o realizar otros ataques que podrían conllevar a filtrados de información o corrupción de la integridad"
    }
  ],
  "lastModified": "2026-06-17T04:09:15.720",
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