high7.1
CVE-2026-48798
SSH.NET: ScpClient Recursive Download Allows Arbitrary File Write via Server-Controlled SCP Filenames
Impact
SSH.NET is a Secure Shell (SSH) library for .NET. In 2025.1.0 and earlier, ScpClient.Download(string directoryName, DirectoryInfo directoryInfo) trusts file and directory names returned by a remote SCP server and combines them with the requested local directory without containment validation, allowing a malicious, compromised, or man-in-the-middle server to use ../ sequences or absolute paths to create or overwrite files anywhere writable by the client process. This issue is fixed in version 2026.0.0.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| nuget | SSH.NET | <= 2025.1.0 | 2026.0.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-q939-rpr3-3284
- https://github.com/sshnet/SSH.NET/security/advisories/GHSA-q939-rpr3-3284
- https://github.com/sshnet/SSH.NET/commit/600be0de543765995a189b5d7cd4efac5007f3ce
- https://nvd.nist.gov/vuln/detail/CVE-2026-48798
- https://github.com/sshnet/SSH.NET/releases/tag/2026.0.0