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CWE-135 — Incorrect Calculation of Multi-Byte String Length

provenance: imported · CWE: CWE-135

CWE-135: Incorrect Calculation of Multi-Byte String Length

MITRE CWE weakness

Kind Weakness
Abstraction Base
Status Draft
Likelihood of exploit

Description

The product does not correctly calculate the length of strings that can contain wide or multi-byte characters.

Common consequences

  • Integrity, Confidentiality, Availability: Execute Unauthorized Code or Commands
  • Availability, Confidentiality: Read Memory, DoS: Crash, Exit, or Restart, DoS: Resource Consumption (CPU), DoS: Resource Consumption (Memory)
  • Confidentiality: Read Memory

Mitigations

Implementation — Always verify the length of the string unit character.

Implementation — Use length computing functions (e.g. strlen, wcslen, etc.) appropriately with their equivalent type (e.g.: byte, wchar_t, etc.)

References

  • CWE page: https://cwe.mitre.org/data/definitions/135.html
  • CWE list: https://cwe.mitre.org/data/index.html