CVE-2026-85756

SSH.NET is a Secure Shell (SSH) library for .NET. Prior to 2026.0.0, ScpClient places caller-supplied remote paths into the command used to run scp on the server, and the default RemotePathTransformation.DoubleQuote transformation cannot safely quote every remote command interpreter. When an application passes an attacker-controlled path to a shell-based server, shell metacharacters not neutralized by the active IRemotePathTransformation can execute commands as the authenticated SSH user. Exploitation requires a shell-based server and a path crafted for that shell's parsing rules; non-shell servers and paths fully neutralized by the selected transformation are not affected. RemotePathTransformation.ShellQuote is available for POSIX shells, while SftpClient avoids a remote shell entirely. This issue is fixed in version 2026.0.0.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/sshnet/SSH.NET/commit/c66b9f8fb06c12e71761e58a577b1e796026310f
https://github.com/sshnet/SSH.NET/releases/tag/2026.0.0
https://github.com/sshnet/SSH.NET/security/advisories/GHSA-mggc-4xg6-vcxf

Configurations

No configuration.

History

16 Sep 2026, 17:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 17:18

Updated : 2026-09-16 19:17

NVD link : CVE-2026-85756

Mitre link : CVE-2026-85756

CVE.ORG link : CVE-2026-85756

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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