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SY0-501 · Question #359

SY0-501 Question #359: Real Exam Question with Answer & Explanation

The correct answer is C: SSLv3.0 with CBC mode cipher. POODLE Attack Explanation POODLE (Padding Oracle On Downgraded Legacy Encryption) specifically targets SSLv3.0 using CBC (Cipher Block Chaining) mode, exploiting a vulnerability in how SSLv3 handles padding validation - the protocol accepts arbitrary padding bytes without proper

Submitted by thandi_sa· Mar 4, 2026Threats, vulnerabilities, and mitigations

Question

The POODLE attack is an MITM exploit that affects:

Options

  • ATLS1.0 with CBC mode cipher
  • BSSLv2.0 with CBC mode cipher
  • CSSLv3.0 with CBC mode cipher
  • DSSLv3.0 with ECB mode cipher

Explanation

POODLE Attack Explanation

POODLE (Padding Oracle On Downgraded Legacy Encryption) specifically targets SSLv3.0 using CBC (Cipher Block Chaining) mode, exploiting a vulnerability in how SSLv3 handles padding validation - the protocol accepts arbitrary padding bytes without proper verification, allowing an attacker to decrypt secure cookies and session tokens.

Why the distractors are wrong:

  • Option A (TLS 1.0/CBC) is incorrect because POODLE targets SSLv3, not TLS 1.0 - although a later variant called "POODLE for TLS" exists, the original attack is SSLv3-specific
  • Option B (SSLv2.0/CBC) is wrong because SSLv2 uses a different (MAC-then-encrypt) structure and POODLE exploits SSLv3's specific padding behavior
  • Option D (SSLv3.0/ECB) is incorrect because ECB (Electronic Codebook) mode doesn't use chaining or padding in the same exploitable way; the padding oracle attack only works against CBC mode

Memory Tip: Think "POODLE bites SSL3 blocks" - the attack bites (exploits) SSLv3 and requires block cipher (CBC) mode to execute the padding oracle technique. If you remember that POODLE forces a downgrade to SSLv3, the CBC component logically follows as the exploitable cipher mode.

Topics

#POODLE attack#SSL/TLS vulnerabilities#Cryptography#Man-in-the-Middle (MITM)

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