Failure of true random number generator

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This is a Vulnerability. To view all vulnerabilities, please see the Vulnerability Category page.



Contents


ASDR Table of Contents

Last revision (mm/dd/yy): 11/2/2008


Description

True random number generators generally have a limited source of entropy and therefore can fail or block.

Consequences

  • Availability: A program may crash or block if it runs out of random numbers.

Exposure period

  • Requirements specification: Choose an operating system which is aggressive and effective at generating true random numbers.
  • Implementation: This type of failure is a logical flaw which can be exacerbated by a lack of or the misuse of mitigating technologies.

Platform

  • Languages: Any
  • Operating platforms: Any

Required resources

Any

Severity

Medium

Likelihood of exploit

Low to Medium

The rate at which true random numbers can be generated is limited. It is important that one uses them only when they are needed for security.


Risk Factors

TBA

Examples

In C:

while (1){
  if (connection){
    if (hwRandom()){
      //use the random bytes
    }
    else (hwRandom()) {
      //cancel the program
  } 
}


Related Attacks


Related Vulnerabilities


Related Controls

  • Implementation: Rather than failing on a lack of random numbers, it is often preferable to wait for more numbers to be created.


Related Technical Impacts


References

TBD