Description
The application subtracts one pointer from another in order to determine size, but this calculation can be incorrect if the pointers do not exist in the same memory chunk.
Modes of Introduction:
– Implementation
Likelihood of Exploit: Medium
Related Weaknesses
Consequences
Access Control, Integrity, Confidentiality, Availability: Modify Memory, Read Memory, Execute Unauthorized Code or Commands, Gain Privileges or Assume Identity
There is the potential for arbitrary code execution with privileges of the vulnerable program.
Potential Mitigations
Phase: Implementation
Description:
Save an index variable. This is the recommended solution. Rather than subtract pointers from one another, use an index variable of the same size as the pointers in question. Use this variable to “walk” from one pointer to the other and calculate the difference. Always validate this number.