"ciphertext-only attack" meaning in English

{
  "forms": [
    {
      "form": "ciphertext-only attacks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "ciphertext-only attack (plural ciphertext-only attacks)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
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        },
        {
          "kind": "other",
          "name": "Terms with Finnish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Cryptography",
          "orig": "en:Cryptography",
          "parents": [
            "Computer science",
            "Formal sciences",
            "Mathematics",
            "Computing",
            "Sciences",
            "Technology",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "coordinate_terms": [
        {
          "word": "known-plaintext attack"
        },
        {
          "word": "chosen-plaintext attack"
        },
        {
          "word": "chosen-ciphertext attack"
        }
      ],
      "glosses": [
        "An attack on a cryptosystem that relies only on the attacker's knowledge of some ciphertexts encrypted with that system and key. Less powerful than a known-plaintext attack."
      ],
      "id": "en-ciphertext-only_attack-en-noun-BDktyl8k",
      "links": [
        [
          "cryptography",
          "cryptography"
        ],
        [
          "attack",
          "attack"
        ],
        [
          "cryptosystem",
          "cryptosystem"
        ],
        [
          "ciphertext",
          "ciphertext"
        ],
        [
          "known-plaintext attack",
          "known-plaintext attack"
        ]
      ],
      "raw_glosses": [
        "(cryptography) An attack on a cryptosystem that relies only on the attacker's knowledge of some ciphertexts encrypted with that system and key. Less powerful than a known-plaintext attack."
      ],
      "synonyms": [
        {
          "word": "known-ciphertext attack"
        },
        {
          "tags": [
            "initialism"
          ],
          "word": "COA"
        }
      ],
      "topics": [
        "computing",
        "cryptography",
        "engineering",
        "mathematics",
        "natural-sciences",
        "physical-sciences",
        "sciences"
      ],
      "translations": [
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "cryptanalytic attack",
          "word": "vain salatekstiin perustuva hyökkäys"
        }
      ],
      "wikipedia": [
        "en:ciphertext-only attack"
      ]
    }
  ],
  "word": "ciphertext-only attack"
}

{
  "coordinate_terms": [
    {
      "word": "known-plaintext attack"
    },
    {
      "word": "chosen-plaintext attack"
    },
    {
      "word": "chosen-ciphertext attack"
    }
  ],
  "forms": [
    {
      "form": "ciphertext-only attacks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "ciphertext-only attack (plural ciphertext-only attacks)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Entries with translation boxes",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Finnish translations",
        "en:Cryptography"
      ],
      "glosses": [
        "An attack on a cryptosystem that relies only on the attacker's knowledge of some ciphertexts encrypted with that system and key. Less powerful than a known-plaintext attack."
      ],
      "links": [
        [
          "cryptography",
          "cryptography"
        ],
        [
          "attack",
          "attack"
        ],
        [
          "cryptosystem",
          "cryptosystem"
        ],
        [
          "ciphertext",
          "ciphertext"
        ],
        [
          "known-plaintext attack",
          "known-plaintext attack"
        ]
      ],
      "raw_glosses": [
        "(cryptography) An attack on a cryptosystem that relies only on the attacker's knowledge of some ciphertexts encrypted with that system and key. Less powerful than a known-plaintext attack."
      ],
      "topics": [
        "computing",
        "cryptography",
        "engineering",
        "mathematics",
        "natural-sciences",
        "physical-sciences",
        "sciences"
      ],
      "wikipedia": [
        "en:ciphertext-only attack"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "known-ciphertext attack"
    },
    {
      "tags": [
        "initialism"
      ],
      "word": "COA"
    }
  ],
  "translations": [
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "cryptanalytic attack",
      "word": "vain salatekstiin perustuva hyökkäys"
    }
  ],
  "word": "ciphertext-only attack"
}