We show that when the attacker has access to an electronic codebook(ECB)oracle,the plaintext cipher block chaining mode(PCBC) can be easily attacked;

• 对分组密码的工作模式进行了攻击,结果表明如果攻击者能询问电码本(ECB)问答器,则很容易攻破明密文分组连接模式(PCBC);