Cygnus Ssh MCP Server
cygnus-ssh-mcp
PyPI
v1.5.1
Published by cygnussystems — no publish provenance, so origin is unverified, but the source is public: the repository link below is self-declared yet readable, so you can inspect the code before adopting it.
The grade answers one question — how safe is this server for you to adopt — so it is computed in two auditable stages. Nothing below is an opinion or an LLM's guess; every line is a real term the deterministic engine applied, and the same input always yields the same number.
1. Threat score — 100 − 0 = 100. What the published surface and source actually contain:
The deterministic scan raised no scored threat in the surface it inspected — the threat score stayed at 100. Capability observations and advisory notes are recorded but never lower it.
2. Client adoption risk — 100 − 4 = 96. Three small, subtract-only factors that reflect your risk in adopting it — a clean scan proves less on a powerful, unverified or barely-inspectable package, so the grade says so plainly:
| Points | Adoption-risk factor |
|---|---|
| −3 | capability blast radius (moderate) — client exposure if the model is manipulated |
| −1 | publisher verification (public source) — no provenance, but the source is public and inspectable |
Capability observations and info notes are shown under Findings but never scored.
Open any row's finding below for the file, line and evidence behind a deduction.
Findings 3
high Reads a sensitive credential path or dumps the environment (src/cygnus_ssh_mcp/server.py)MTC-SRC-006
In the server's implementation (`src/cygnus_ssh_mcp/server.py:319`): Reading private keys / cloud credentials, or serializing the whole environment, is a sensitive-data source that becomes exfiltration when combined with any egress. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: key file (e.g., ~/.ssh/id_rsa)")] = None, key_passphrase: Annotated[Optional[str], Field(description="Passphrase fo
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server src/cygnus_ssh_mcp/server.py
medium Tool "ssh_dir_batch_delete_files" can modify the filesystemMTC-CAP-002
Tool "ssh_dir_batch_delete_files" can write, overwrite or delete files (keyword "delete_file" in tool name). Verify it is scoped to a safe directory.
Fix: Constrain file operations to an explicit, non-sensitive root; reject path traversal.
Location: tool ssh_dir_batch_delete_files
low Mutating tool "ssh_dir_batch_delete_files" declares no destructiveHintMTC-CAP-005
Tool "ssh_dir_batch_delete_files" can mutate/egress but declares no destructiveHint. Clients that don't default to spec-safe behavior may not prompt before running it.
Fix: Declare accurate annotations, and gate destructive tools on user confirmation regardless.
Location: tool ssh_dir_batch_delete_files
Tools 46
Each tool and what it can reach — statically extracted from the published source.
ssh_dir_batch_delete_fileswrites filesssh_dir_list_files_basicreads sensitive datalist_toolsno sensitive capabilityssh_archive_createno sensitive capabilityssh_archive_extractno sensitive capabilityssh_cmd_check_statusno sensitive capabilityssh_cmd_clear_historyno sensitive capabilityssh_cmd_historyno sensitive capabilityssh_cmd_killno sensitive capabilityssh_cmd_outputno sensitive capability
Show 36 more tools ↓
ssh_cmd_runno sensitive capabilityssh_conn_add_hostno sensitive capabilityssh_conn_connectno sensitive capabilityssh_conn_host_infono sensitive capabilityssh_conn_is_connectedno sensitive capabilityssh_conn_statusno sensitive capabilityssh_conn_verify_sudono sensitive capabilityssh_dir_calc_sizeno sensitive capabilityssh_dir_copyno sensitive capabilityssh_dir_deleteno sensitive capabilityssh_dir_list_advancedno sensitive capabilityssh_dir_mkdirno sensitive capabilityssh_dir_removeno sensitive capabilityssh_dir_search_files_contentno sensitive capabilityssh_dir_search_globno sensitive capabilityssh_dir_transferno sensitive capabilityssh_file_copyno sensitive capabilityssh_file_delete_line_by_contentno sensitive capabilityssh_file_find_lines_with_patternno sensitive capabilityssh_file_get_context_around_lineno sensitive capabilityssh_file_insert_lines_after_matchno sensitive capabilityssh_file_moveno sensitive capabilityssh_file_readno sensitive capabilityssh_file_replace_lineno sensitive capabilityssh_file_replace_line_multino sensitive capabilityssh_file_statno sensitive capabilityssh_file_transferno sensitive capabilityssh_file_writeno sensitive capabilityssh_host_disconnectno sensitive capabilityssh_host_listno sensitive capabilityssh_host_removeno sensitive capabilityssh_host_updateno sensitive capabilityssh_host_use_configno sensitive capabilityssh_task_killno sensitive capabilityssh_task_launchno sensitive capabilityssh_task_statusno sensitive capability
What this scan could not see
- Tools were statically extracted from the published source (46 recovered), not enumerated from a running server. Tool-poisoning, Unicode-smuggling, capability and toxic-flow analysis ran on this inferred surface, but a mis-parsed registration could be missed or mis-attributed, so tool-derived findings are capped below “confirmed”. To grade the real runtime surface, scan the running server: --command "npx -y <package>".
Versions 1
Scan history per published version. The engine is deterministic — the same version always yields the same score, so a changed score means the package itself changed.
| Version | Score | Findings | Engine | Scanned |
|---|---|---|---|---|
v1.5.1 latest |
A 96/100 | 3 | 1.9.0 | 2026-07-23 |
Embed this score
Show this server's live Trust Score in your README, docs or website. The badge is served straight from the registry and updates automatically after every rescan — no API key needed. It links back to this page, so anyone who sees the grade can also read the findings behind it instead of taking a number on faith.
Verify this score yourself
The score above is reproducible: the same package version always yields the same result. Run it locally or over the free API — no account, no LLM, fully deterministic.
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