CVE Vulnerabilities

CVE-2021-27499

Use of Insufficiently Random Values

Published: Aug 02, 2021 | Modified: Jun 30, 2023
CVSS 3.x
5.9
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N
RedHat/V2
RedHat/V3
Ubuntu

Ypsomed mylife Cloud, mylife Mobile Application, Ypsomed mylife Cloud: All versions prior to 1.7.2, Ypsomed mylife App: All versions prior to 1.7.5,The application layer encryption of the communication protocol between the Ypsomed mylife App and mylife Cloud uses non-random IVs, which allows man-in-the-middle attackers to tamper with messages.

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
Mylife Ypsomed * 1.7.5 (excluding)
Mylife_cloud Ypsomed * 1.7.2 (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