Cyber Resilience

CVE-2022-29245

MediumPublic PoC

Published: 31 May 2022

Published
31 May 2022
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS Score 0.0045 64.0th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2022-29245 is a medium-severity PRNG (CWE-338) vulnerability in Ssh.Net Project Ssh.Net. Its CVSS base score is 6.5 (Medium).

Operationally, ranked in the top 36.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

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…

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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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

ssh.net project
ssh.net
2020.0.0, 2020.0.1

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-338

Security associations share details on cryptographically weak PRNGs, helping avoid their implementation in security-critical functions.

addresses: CWE-338

Cryptographic key management standards require cryptographically strong PRNGs for key material, blocking use of weak generators.

References