Description
SSH.NET is a Secure Shell (SSH) library for .NET. In versions 2020.0.0 and 2020.0.1, during an `X25519` key exchange, the client’s private key is generated with `System.Random`. `System.Random` is not a cryptographically secure random number generator, it must therefore not be used for cryptographic purposes. When establishing an SSH connection to a remote host, during the X25519 key exchange, the private key is generated with a weak random number generator whose seed can be brute forced. This allows an attacker who is able to eavesdrop on the communications to decrypt them. Version 2020.0.2 contains a patch for this issue. As a workaround, one may disable support for `curve25519-sha256` and `[email protected]` key exchange algorithms.
Scores
CVSS v3
6.5
EPSS
0.0032
EPSS Percentile
54.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-338
Status
published
Products (3)
nuget/SSH.NET
0 - 2020.0.2NuGet
ssh.net_project/ssh.net
2020.0.0 (2 CPE variants)
ssh.net_project/ssh.net
2020.0.1
Published
May 31, 2022
Tracked Since
Feb 18, 2026