# GHSA-j7h9-2jh7-g967: mcp-ssh-tool has file transfer path policy bypass and bearer token comparison hardening

> Attackers can bypass file transfer path restrictions and exploit timing side channels in authentication, potentially accessing unauthorized files.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 May 2026

## What is GHSA-j7h9-2jh7-g967?

GHSA-j7h9-2jh7-g967 is a path traversal vulnerability in mcp-ssh-tool, published on 7 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

## Summary

`mcp-ssh-tool` has released version `2.1.1` with security hardening for transfer path authorization and HTTP bearer authentication.

The release addresses:

- insufficient local path policy enforcement in transfer-related filesystem handling
- incomplete canonicalization and segment-boundary handling for deny-prefix path policy checks
- non-constant-time HTTP bearer token comparison

## Impact

Affected versions may allow policy bypass in transfer path handling under specific configurations, and may expose a timing side channel in bearer-token comparison for HTTP deployments.

## Patched Version

Upgrade to `mcp-ssh-tool >= 2.1.1`.

```bash
npm install -g mcp-ssh-tool@latest
```

## Workarounds

For deployments that cannot immediately upgrade:

- avoid exposing HTTP transport beyond loopback
- use strict filesystem policy configuration
- avoid granting MCP clients access to sensitive local transfer paths
- monitor audit logs for unexpected transfer operations

## Credits

Reported by `dodge1218`.

## Which versions are affected by GHSA-j7h9-2jh7-g967?

2 open source packages ship an affected version, including mcp-ssh-tool.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mcp-ssh-tool` | npm | All versions | 2.1.1 |
| `mcp-ssh-tool` | npm | All versions | 2.1.1 |

## How do I fix GHSA-j7h9-2jh7-g967?

Upgrade mcp-ssh-tool to 2.1.1 or later.

## Is GHSA-j7h9-2jh7-g967 being exploited?

There is no known exploitation of GHSA-j7h9-2jh7-g967 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-j7h9-2jh7-g967 and fix it if it is affected.

What it is: GHSA-j7h9-2jh7-g967 is a path traversal vulnerability in mcp-ssh-tool, published on 7 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-j7h9-2jh7-g967 in the wild and no public exploit code.

Affected packages and fixed versions:
- mcp-ssh-tool (npm): affected all versions; fixed in 2.1.1
- mcp-ssh-tool (npm): affected all versions; fixed in 2.1.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/GHSA-j7h9-2jh7-g967/ (Markdown: https://insights.sbomify.com/GHSA-j7h9-2jh7-g967/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-j7h9-2jh7-g967

---
From sbomify Insights: https://insights.sbomify.com/GHSA-j7h9-2jh7-g967/
Summaries are generated and may contain mistakes; the official description above is the record.