CVE Vulnerabilities

CVE-2017-17845

Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

Published: Dec 27, 2017 | Modified: Nov 07, 2023
CVSS 3.x
7.3
HIGH
Source:
NVD
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CVSS 2.x
7.5 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu
LOW

An issue was discovered in Enigmail before 1.9.9. Improper Random Secret Generation occurs because Math.Random() is used by pretty Easy privacy (pEp), aka TBE-01-001.

Weakness

The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG’s algorithm is not cryptographically strong.

Affected Software

Name Vendor Start Version End Version
Enigmail Enigmail * 1.9.9 (excluding)
Enigmail Ubuntu artful *
Enigmail Ubuntu trusty *
Enigmail Ubuntu upstream *
Enigmail Ubuntu xenial *
Enigmail Ubuntu zesty *

Extended Description

When a non-cryptographic PRNG is used in a cryptographic context, it can expose the cryptography to certain types of attacks. Often a pseudo-random number generator (PRNG) is not designed for cryptography. Sometimes a mediocre source of randomness is sufficient or preferable for algorithms that use random numbers. Weak generators generally take less processing power and/or do not use the precious, finite, entropy sources on a system. While such PRNGs might have very useful features, these same features could be used to break the cryptography.

Potential Mitigations

References