Chosen-ciphertext security and decryption access
Research context
postgraduate concept · established · As of 2026-10-10
Adaptive chosen-ciphertext security allows decryption queries before and after a challenge, excluding the challenge ciphertext itself under the experiment's rules.
Key knowledge
Adaptive chosen-ciphertext security allows decryption queries before and after a challenge, excluding the challenge ciphertext itself under the experiment's rules. Plain IND-CPA encryption can fail when malleated ciphertexts produce useful responses. Authenticated encryption or a securely constructed CCA KEM addresses a stronger attack model, but invalid-ciphertext handling, timing and composition must preserve the proof's assumptions.
Conditions and scope
- The adversary's permitted oracle queries and forbidden challenge query are exact game rules.
- A security reduction does not automatically include side channels or reveal secret state after compromise.
Sources · 2
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Author checked this English statement, displayed equation where present and stated hypotheses against these source locations: Encryption games chapters 2–3/9/12, authentication chapters 6–8, signatures chapter 13, reductions and identification/zero knowledge chapters 18–20; §§3.2–3.3 IND-CCA2/failure model and implementation constraints; §§7–8 parameters, Tables 1–3. The check is bounded to the recorded claims; no complete proof reconstruction, software proof replay or universal literature completeness is claimed.
2026-10-10 · Author source-body/statement/equation/domain check, with graph associations scoped individually. Separate independent content/source/inventory review is required before branch closure.
Entry details
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- research-info-encryption-ind-cca
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- Postgraduate & research reference