SC-31 Covert Channel Analysis
Review SC-31
1. Set its parameters
No parameters to set for SC-31.
2. Record its status
a.Perform a covert channel analysis to identify those aspects of communications within the system that are potential avenues for covert [Selection (one-or-more): storage; timing] channels; and
b.Estimate the maximum bandwidth of those channels.
Discussion
Developers are in the best position to identify potential areas within systems that might lead to covert channels. Covert channel analysis is a meaningful activity when there is the potential for unauthorized information flows across security domains, such as in the case of systems that contain export-controlled information and have connections to external networks (i.e., networks that are not controlled by organizations). Covert channel analysis is also useful for multilevel secure systems, multiple security level systems, and cross-domain systems.
Enhancements
Review SC-31(1)
1. Set its parameters
No parameters to set for SC-31(1).
2. Record its status
Test a subset of the identified covert channels to determine the channels that are exploitable.
Discussion
None.
Review SC-31(2)
1. Set its parameters
No parameters to set for SC-31(2).
2. Record its status
Reduce the maximum bandwidth for identified covert [Selection (one-or-more): storage; timing] channels to [Assignment: organization-defined values].
Discussion
The complete elimination of covert channels, especially covert timing channels, is usually not possible without significant performance impacts.
Review SC-31(3)
1. Set its parameters
No parameters to set for SC-31(3).
2. Record its status
Measure the bandwidth of [Assignment: organization-defined subset of identified covert channels] in the operational environment of the system.
Discussion
Measuring covert channel bandwidth in specified operational environments helps organizations determine how much information can be covertly leaked before such leakage adversely affects mission or business functions. Covert channel bandwidth may be significantly different when measured in settings that are independent of the specific environments of operation, including laboratories or system development environments.
No Enhancements match this Baseline.
ISO/IEC 27001:2022 Crosswalk
No ISO 27001 mapping published for this control.