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.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
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.
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 | 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.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
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.