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TI-2026-36068 Aliases CVE-2026-48798GHSA-q939-rpr3-3284

SSH.NET: ScpClient Recursive Download Allows Arbitrary File Write via Server-Controlled SCP Filenames

Priority LOW 32CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00421 36th percentileScored 2026-11-07
Fix Fixed SSH.NET (sshnet): 2026.0.0SSH.NET (NuGet): 2026.0.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
sshnetSSH.NETbefore 2026.0.02026.0.0Patch availableCNA
—SSH.NET (NuGet)before 2026.0.02026.0.0Patch availableGHSA-q939-rpr3-3284
  • SSH.NET Vendorsshnet Affected before 2026.0.0 Fixed in 2026.0.0 Patch available CNA
  • SSH.NET (NuGet) Vendor— Affected before 2026.0.0 Fixed in 2026.0.0 Patch available GHSA-q939-rpr3-3284

Remediation

  • Fix · CNA SSH.NET (sshnet) Fixed in 2026.0.0
  • Fix · GHSA-q939-rpr3-3284 SSH.NET (NuGet) Fixed in 2026.0.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-48798
  2. 2026-10-03 Alias added: GHSA-q939-rpr3-3284

References

Advisory 1

Other 4

  • TI-2026-58836 SSH.NET: ScpClient allows server-side RCE via default SCP path handling CVSS 3.1HIGH 7.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences