BaseDraftCWE-135

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

Description

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

Abstraction: BaseA weakness specific enough to point to detection and prevention methods.
Likelihood of exploit: Not rated by MITRE
Status: Draft

Common consequences

IntegrityConfidentialityAvailability
Execute Unauthorized Code or Commands
This weakness may lead to a buffer overflow. Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy. This can often be used to subvert any other security service.
AvailabilityConfidentiality
Read Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)
Out of bounds memory access will very likely result in the corruption of relevant memory, and perhaps instructions, possibly leading to a crash. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.
Confidentiality
Read Memory
In the case of an out-of-bounds read, the attacker may have access to sensitive information. If the sensitive information contains system details, such as the current buffer's position in memory, this knowledge can be used to craft further attacks, possibly with more severe consequences.

Potential mitigations

ImplementationInput Validation
Always verify the length of the string unit character.
ImplementationLibraries or Frameworks
Use length computing functions (e.g. strlen, wcslen, etc.) appropriately with their equivalent type (e.g.: byte, wchar_t, etc.)

Related weaknesses

Parent weaknesses

CWE-682Incorrect Calculation

CAPEC attack patterns that exploit it

CWE 4.20 links no CAPEC attack pattern to this weakness.

Common consequences

IntegrityConfidentialityAvailability

Execute Unauthorized Code or Commands

This weakness may lead to a buffer overflow. Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy. This can often be used to subvert any other security service.

AvailabilityConfidentiality

Read Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory)

Out of bounds memory access will very likely result in the corruption of relevant memory, and perhaps instructions, possibly leading to a crash. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.

Confidentiality

Read Memory

In the case of an out-of-bounds read, the attacker may have access to sensitive information. If the sensitive information contains system details, such as the current buffer's position in memory, this knowledge can be used to craft further attacks, possibly with more severe consequences.