• Requirement

    Account for timing interactions among system components in determining appropriate responses for invalid inputs.

  • Discussion

    In addressing invalid system inputs received across protocol interfaces, timing interactions become relevant, where one protocol needs to consider the impact of the error response on other protocols in the protocol stack. For example, 802.11 standard wireless network protocols do not interact well with Transmission Control Protocols (TCP) when packets are dropped (which could be due to invalid packet input). TCP assumes packet losses are due to congestion, while packets lost over 802.11 links are typically dropped due to noise or collisions on the link. If TCP makes a congestion response, it takes the wrong action in response to a collision event. Adversaries may be able to use what appear to be acceptable individual behaviors of the protocols in concert to achieve adverse effects through suitable construction of invalid input. The invalid inputs are those related to the information inputs defined by the organization in the base control (SI-10).

More Info

  • Title

    Information Input Validation | Timing Interactions
  • Family

    System and Information Integrity
  • NIST 800-53B Baseline(s)

    • Related NIST 800-53 ID

    NIST 800-53A Assessment Guidance

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