CVE-2026-85756 (GCVE-0-2026-85756)

Vulnerability from cvelistv5 – Published: 2026-09-16 16:31 – Updated: 2026-09-16 18:34
VLAI
Title
SSH.NET: ScpClient allows server-side RCE via default SCP path handling
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-16 18:21 UTC
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7775 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
sshnet SSH.NET Affected: < 2026.0.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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