COMMON WEAKNESS ENUMERATIONDraft

CWE-341

Predictable from Observable State

A number or object is predictable based on observations that the attacker can make about the state of the system or network, such as time, process ID, etc.

Soyutlama

Base

Yapı

Simple

Sömürü İhtimali

Medium

Problemi anla

Problem nedir?

A number or object is predictable based on observations that the attacker can make about the state of the system or network, such as time, process ID, etc.

Kök neden

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Yaşam döngüsü evresi

Architecture and Design

Yaşam döngüsü evresi

Implementation

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

Risk

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Varies by Context

Etkilenen güvenlik alanları: Other

This weakness could be exploited by an attacker in a number ways depending on the context. If a predictable number is used to generate IDs or keys that are used within protection mechanisms, then an attacker could gain unauthorized access to the system. If predictable filenames are used for storing sensitive information, then an attacker might gain access to the system and may be able to gain access to the information in the file.

Savunma

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Implementation

Uygulama aşaması savunması

Detay
Increase the entropy used to seed a PRNG.

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. Consult FIPS 140-2 Annex C ("Approved Random Number Generators").

Implementation

Uygulama aşaması savunması

Detay
Use a PRNG that periodically re-seeds itself using input from high-quality sources, such as hardware devices with high entropy. However, do not re-seed too frequently, or else the entropy source might block.

Doğrulama

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Automated Static Analysis

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.)