CVE-2022-29245

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 clientâ€™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 `curve25519-sha256@libssh.org` key exchange algorithms.

CVSS v3.0 5.9 MEDIUM
CVSS v2.0 4.3 MEDIUM

5.9^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

4.3^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:M/Au:N/C:P/I:N/A:N

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://github.com/sshnet/SSH.NET/security/advisories/GHSA-72p8-v4hg-v45p	Exploit Mitigation Third Party Advisory
https://github.com/sshnet/SSH.NET/releases/tag/2020.0.2	Release Notes Third Party Advisory
https://github.com/sshnet/SSH.NET/blob/bc99ada7da3f05f50d9379f2644941d91d5bf05a/src/Renci.SshNet/Security/KeyExchangeECCurve25519.cs#L51	Exploit Third Party Advisory
https://github.com/sshnet/SSH.NET/commit/03c6d60736b8f7b42e44d6989a53f9b644a091fb	Patch Third Party Advisory

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Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:ssh.net_project:ssh.net:2020.0.0:beta1::::.net::*
	cpe:2.3:a:ssh.net_project:ssh.net:2020.0.1:::::.net::
	cpe:2.3:a:ssh.net_project:ssh.net:2020.0.0:-::::.net::*

Information

Published : 2022-05-31 10:15

Updated : 2022-06-14 15:39

NVD link : CVE-2022-29245

Mitre link : CVE-2022-29245

JSON object : View

CWE

CWE-338

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

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Products Affected

ssh.net_project

ssh.net

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