COMMON WEAKNESS ENUMERATIONDraft

CWE-336

Same Seed in Pseudo-Random Number Generator (PRNG)

A Pseudo-Random Number Generator (PRNG) uses the same seed each time the product is initialized.

Soyutlama

Variant

Yapı

Simple

Sömürü İhtimali

Medium

Problemi anla

Problem nedir?

A Pseudo-Random Number Generator (PRNG) uses the same seed each time the product is initialized.

Genişletilmiş açıklama

Given the deterministic nature of PRNGs, using the same seed for each initialization will lead to the same output in the same order. If an attacker can guess (or knows) the seed, then the attacker may be able to determine the random numbers that will be produced from the PRNG.

Kök neden

Problem nasıl ve ne zaman oluşur?

Yaşam döngüsü evresi

Implementation

REALIZATION: This weakness is caused during implementation of an architectural security tactic.

Risk

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OtherBypass Protection Mechanism

Etkilenen güvenlik alanları: Other, Access Control

Savunma

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Architecture and Design

Mimari ve tasarım yaklaşımı

Detay
Do not reuse PRNG seeds. Consider a PRNG that periodically re-seeds itself as needed from a high quality pseudo-random output, such as hardware devices.

Architecture and Design · Requirements

Libraries or Frameworks

Detay
Use products or modules that conform to FIPS 140-2 [REF-267] to avoid obvious entropy problems, or use the more recent FIPS 140-3 [REF-1192] if possible.

Doğrulama

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Automated Static Analysis

High
Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)