Open-Source Security Intelligence

Know every vulnerability
before it knows you.

DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.

Search

GHSA-mggc-4xg6-vcxf

HighCVSS 7.5 / 10
Published Sep 17, 2026·Last modified Sep 17, 2026
Affected Components(1)
NuGet logoSSH.NET
< 2026.0.0
Description

Summary

Default SCP remote-path handling places caller-supplied paths into the command that runs scp on the server. On a shell-based server that command is interpreted by a shell, so an attacker-influenced path that is not quoted to suit that shell can execute as a command as the authenticated SSH user. SSH.NET provides ScpClient.RemotePathTransformation to control escaping behaviour (defaulting to RemotePathTransformation.DoubleQuote) but cannot guarantee safety for arbitrary remote command interpreters. This is inherent to running scp over a remote shell (cf. CVE-2020-15778).

Impact

Command execution on the SSH server as the authenticated SSH user, when an application passes an attacker-influenced remote path to ScpClient against a shell-based server.

Exploitation depends on conditions beyond the attacker's control: the remote server must be shell-based, and the attacker-influenced path must be crafted to defeat the quoting applied by the transformation in effect — that is, to use metacharacters that it does not neutralise (for example $(...) or backticks, which survive the default double-quoting on a POSIX shell). A path that does not meet these escaping rules, or a non-shell-based server, does not result in command execution.

Remediation

The fixed release obsoletes the constructors that silently defaulted the path transformation and adds constructors that require an explicit IRemotePathTransformation, so callers are required to choose one that suits their server and trust environment. For POSIX shells, the library provides RemotePathTransformation.ShellQuote. The legacy default (RemotePathTransformation.DoubleQuote) is unchanged for backwards compatibility. SCP is considered legacy and SFTP, which does not involve a remote shell, is recommended where possible (via SftpClient).

Upload your SBOM

Upload your own SBOM in CycloneDX 1.6 or higher (JSON) directly here to check your vulnerabilities.

Risk Scores
Base Score
7.5

The vulnerability can be exploited over the network without needing physical access. It is difficult for an attacker to exploit this vulnerability and may require special conditions. An attacker needs basic access or low-level privileges. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data. There is a high impact on the availability of the system.

Threat Intelligence
6.9

Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.

EPSS
0.62%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

Browse More

Scan your project

Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.

Checkout DevGuard