CVE-2026-48798

high

Description

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.

References

https://github.com/sshnet/SSH.NET/security/advisories/GHSA-q939-rpr3-3284

https://github.com/sshnet/SSH.NET/releases/tag/2026.0.0

https://github.com/sshnet/SSH.NET/commit/600be0de543765995a189b5d7cd4efac5007f3ce

Details

Source: Mitre, NVD

Published: 2026-08-18

Updated: 2026-08-18

Risk Information

CVSS v2

Base Score: 8.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:C/A:P

Severity: High

CVSS v3

Base Score: 7.1

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L

Severity: High

EPSS

EPSS: 0.00421