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CVE-2021-34550

Status: ModifiedHigh (7.5)—

An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-006. The v3 onion service descriptor parsing allows out-of-bounds memory access, and a client crash, via a crafted onion service descriptor

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 (1)

Torproject — TOR

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2021-34550",
  "cveTags": [],
  "metrics": {
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        "source": "nvd@nist.gov",
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          "baseScore": 5,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "NONE"
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        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 10,
        "obtainUserPrivilege": false,
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          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
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  "published": "2021-06-29T12:15:08.670",
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      "tags": [
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      "source": "cve@mitre.org"
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "description": [
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          "value": "CWE-119"
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      "lang": "en",
      "value": "An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-006. The v3 onion service descriptor parsing allows out-of-bounds memory access, and a client crash, via a crafted onion service descriptor"
    },
    {
      "lang": "es",
      "value": "Se ha detectado un problema en Tor versiones anteriores a 0.4.6.5, también se conoce como TROVE-2021-006. El análisis del descriptor del servicio de v3 onion, permite un acceso a la memoria fuera de límites, y un bloqueo del cliente, por medio de un descriptor de servicio onion diseñado"
    }
  ],
  "lastModified": "2026-06-17T03:56:06.427",
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    {
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