Improper JPAKE implementation allows offline PIN brute-forcing due to the initialization of random values to a known value, which leads to unauthorized authentication to amzn.lightning services.
This issue affects:
Amazon Fire TV Stick 3rd gen versions prior to 6.2.9.5.
Insignia TV with FireOS 7.6.3.3.
Weakness
The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.
Affected Software
| Name |
Vendor |
Start Version |
End Version |
| Fire_os |
Amazon |
* |
6.2.9.5 (excluding) |
Potential Mitigations
- Use a well-vetted algorithm that is currently considered to be strong by experts in the field, and select well-tested implementations with adequate length seeds.
- In general, if a pseudo-random number generator is not advertised as being cryptographically secure, then it is probably a statistical PRNG and should not be used in security-sensitive contexts.
- Pseudo-random number generators can produce predictable numbers if the generator is known and the seed can be guessed. A 256-bit seed is a good starting point for producing a “random enough” number.
References