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CWE WEAKNESSES  /  CWE-121

CWE-121

Stack-based Buffer Overflow

Variant EXPLOIT LIKELIHOOD: HIGH

What it is

A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).

Impact

AvailabilityModify Memory, DoS: Crash, Exit, or Restart, DoS: Resource Consumption (CPU), DoS: Resource Consumption (Memory)
Integrity, Confidentiality, Availability, Access ControlModify Memory, Execute Unauthorized Code or Commands, Bypass Protection Mechanism
Integrity, Confidentiality, Availability, Access Control, OtherModify Memory, Execute Unauthorized Code or Commands, Bypass Protection Mechanism, Other

Mitigations

  • [Operation, Build and Compilation]Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] dis
  • [Architecture and Design] Use an abstraction library to abstract away risky APIs. Not a complete solution.
  • [Implementation] Implement and perform bounds checking on input.
  • [Implementation] Do not use dangerous functions such as gets. Use safer, equivalent functions which check for boundary errors.
  • [Operation, Build and Compilation]Run or compile the software using features or extensions that randomly arrange the positions of a program's executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Im

Real-world CVE examples

  • CVE-2021-35395 — Stack-based buffer overflows in SFK for wifi chipset used for IoT/embedded devices, as exploited in the wild per CISA KEV.

Related weaknesses

Test & detect

Browse all common weaknesses, check related exploited CVEs, or map to ATT&CK techniques.

Source: MITRE CWE. View on cwe.mitre.org →

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