# What is a popular entropy source for seeding a CSPRNG, which is actually weak and unreliable? [closed]

Say I want to seed a CSPRNG. What sources are popular, but unreliable? What sources should I even use?

• it will be good to combine this with your previous question. – hardyrama Sep 1 '19 at 3:16
• Any language-specific rand() is commonly (mis)used as a cryptographic seed. – forest Sep 1 '19 at 7:30
• Using the current time and date is popular, but unreliable. Oh, abd also totally insecure. – Frank Denis Sep 1 '19 at 16:20

• Do you have "What sources are popular, but unreliable?" the right way around? Lava lamps are a pretty perfect source of entropy (Rayleigh–Bénard convection/deterministic chaotic systems). I also suggest changing to /dev/random if you're looking for perfect but unreliable entropy sources. – Paul Uszak Sep 1 '19 at 23:39