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CVE-2021-30496

Status: ModifiedMedium (5.7)—

The Telegram app 7.6.2 for iOS allows remote authenticated users to cause a denial of service (application crash) if the victim pastes an attacker-supplied message (e.g., in the Persian language) into a channel or group. The crash occurs in MtProtoKitFramework. NOTE: the vendor's perspective is that "this behavior can't be considered a vulnerability."

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)

Telegram — Telegram

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2021-30496",
  "cveTags": [
    {
      "tags": [
        "disputed"
      ],
      "sourceIdentifier": "cve@mitre.org"
    }
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  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
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          "role": "CISA Coordinator",
          "options": [
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              "exploitation": "poc"
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              "automatable": "no"
            },
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            }
          ],
          "version": "2.0.3",
          "timestamp": "2024-05-01T14:44:16.196509Z"
        }
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    ],
    "cvssMetricV2": [
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        "source": "nvd@nist.gov",
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          "baseScore": 3.5,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:M/Au:S/C:N/I:N/A:P",
          "authentication": "SINGLE",
          "integrityImpact": "NONE",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "NONE"
        },
        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "LOW",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 6.8,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": true
      }
    ],
    "cvssMetricV31": [
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        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
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          "attackVector": "NETWORK",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "REQUIRED",
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          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
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  "affected": [
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          "product": "n/a",
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      "affectedData": [
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          "vendor": "telegram",
          "product": "telegram",
          "versions": [
            {
              "status": "affected",
              "version": "7.6.2"
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          "defaultStatus": "unknown"
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  ],
  "published": "2021-04-20T16:15:10.590",
  "references": [
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      "tags": [
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        "Third Party Advisory"
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      "tags": [
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      "source": "cve@mitre.org"
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      "tags": [
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "description": [
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      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "description": [
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          "value": "CWE-121"
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  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "The Telegram app 7.6.2 for iOS allows remote authenticated users to cause a denial of service (application crash) if the victim pastes an attacker-supplied message (e.g., in the Persian language) into a channel or group. The crash occurs in MtProtoKitFramework. NOTE: the vendor's perspective is that \"this behavior can't be considered a vulnerability.\""
    },
    {
      "lang": "es",
      "value": "** EN DISPUTA ** La aplicación Telegram versión 7.6.2 para iOS, permite a usuarios autenticados remoto causar una denegación de servicio (bloqueo de la aplicación) si la víctima pega un mensaje proporcionado por el atacante (por ejemplo, en el idioma Persian) en un canal o grupo. El bloqueo ocurre en la función MtProtoKitFramework. NOTA: la perspectiva del proveedor es que \"este comportamiento no puede considerarse una vulnerabilidad\""
    }
  ],
  "lastModified": "2026-06-17T03:50:20.403",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
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              "vulnerable": true,
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            }
          ],
          "operator": "OR"
        }
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  "sourceIdentifier": "cve@mitre.org"
}