Vulnerability details
CVE-2026-85756
SSH.NET: ScpClient allows server-side RCE via default SCP path handling
Official description
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 scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.5High | 3.1 | CVEProject cvelistV5 (CNA) (GitHub_M) | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| sshnet | SSH.NET | < 2026.0.0 | CVEProject cvelistV5 (CNA) |
References and advisories
3- https://github.com/sshnet/SSH.NET/security/advisories/GHSA-mggc-4xg6-vcxf x_refsource_CONFIRM
- https://github.com/sshnet/SSH.NET/commit/c66b9f8fb06c12e71761e58a577b1e796026310f x_refsource_MISC
- https://github.com/sshnet/SSH.NET/releases/tag/2026.0.0 x_refsource_MISC
Details
- Published
- 2026-09-16
- Last updated
- 2026-09-16
- State
- Published
- Assigner (CNA)
- GitHub_M
Exploit prediction (EPSS)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- None
- Technical impact
- Total
Weaknesses (CWE)
- CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')