CVE-2026-48798 (GCVE-0-2026-48798)

Vulnerability from cvelistv5 – Published: 2026-08-18 14:57 – Updated: 2026-08-18 15:28
VLAI
Title
SSH.NET: ScpClient Recursive Download Allows Arbitrary File Write via Server-Controlled SCP Filenames
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.
Severity
7.1 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-18 15:28 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-73 - External Control of File Name or Path
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8035 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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