A replay attack is where a valid message is intercepted and replayed back to the service.

重播攻击是这样一类攻击：它可以拦截有效的消息，然后再将该消息重播回服务。

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Replay attack — Re-sending a previously valid message for malicious effect, possibly where only parts of the message (such as the security token) are replayed.

应答攻击——为实现恶意的效果，重新发送一个以前曾经有效的消息，其中可能只是重放部分消息(如安全令牌)。

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This attack can be combined with Replay attack to bypass authentication, and with Single message XDoS to increase its impact.

这种攻击可以与应答攻击联合使用，以绕过身份验证，并且再加上单消息 XDoS 来增加其危害程度。

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