CVE Vulnerabilities

CVE-2021-25444

Use of Insufficiently Random Values

Published: Aug 05, 2021 | Modified: Aug 01, 2022
CVSS 3.x
5.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVSS 2.x
2.1 LOW
AV:L/AC:L/Au:N/C:P/I:N/A:N
RedHat/V2
RedHat/V3
Ubuntu

An IV reuse vulnerability in keymaster prior to SMR AUG-2021 Release 1 allows decryption of custom keyblob with privileged process.

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
Android Google 8.1 8.1
Android Google 9.0 9.0
Android Google 10.0 10.0

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