CWE-336 PRNG中使用相同种子

Same Seed in Pseudo-Random Number Generator (PRNG)

结构: Simple

Abstraction: Variant

状态: Draft

被利用可能性: unkown


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


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.


  • cwe_Nature: ChildOf cwe_CWE_ID: 335 cwe_View_ID: 1000 cwe_Ordinal: Primary

  • cwe_Nature: ChildOf cwe_CWE_ID: 335 cwe_View_ID: 699 cwe_Ordinal: Primary


Language: {'cwe_Class': 'Language-Independent', 'cwe_Prevalence': 'Undetermined'}


范围 影响 注释
['Other', 'Access Control'] ['Other', 'Bypass Protection Mechanism']


Architecture and Design


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.

MIT-2 ['Architecture and Design', 'Requirements']

策略: Libraries or Frameworks

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").


The following code uses a statistical PRNG to generate account IDs.

bad Java

private static final long SEED = 1234567890;
public int generateAccountID() {
Random random = new Random(SEED);
return random.nextInt();

Because the program uses the same seed value for every invocation of the PRNG, its values are predictable, making the system vulnerable to attack.


映射的分类名 ImNode ID Fit Mapped Node Name
PLOVER Same Seed in PRNG
The CERT Oracle Secure Coding Standard for Java (2011) MSC02-J Generate strong random numbers