{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@aiondadotcom/mcp-ssh"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.3.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-78",
      "CWE-88"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-14T00:04:10Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "## Impact\n\nA crafted `hostAlias` argument such as `-oProxyCommand=...` was passed to `ssh`/`scp` without an argument terminator. SSH interprets arguments starting with `-` as options regardless of position, so the option-injection caused SSH to execute the attacker-supplied `ProxyCommand` **locally** on the machine running the MCP server \u2014 before any network connection. This bypassed the documented protection of `# @password:` annotations and exposed local SSH keys, browser cookies, other MCP server credentials, and anything else readable by the server process.\n\nA second local-RCE vector existed on Windows: `spawn(..., { shell: true })` was used so that `ssh.exe`/`scp.exe` could be found via `PATH`. With `shell: true`, every argument is re-parsed by `cmd.exe`, so shell metacharacters (`\u0026`, `|`, `^`, `\u003e`, `\"`, `;`, \u2026) in `hostAlias`, `command`, `localPath` or `remotePath` would have been interpreted by `cmd.exe` and could have triggered arbitrary local command execution on Windows.\n\nThe MCP server runs locally over STDIO, but the LLM driving it is not trusted: its tool arguments can be steered by **prompt injection** from any untrusted text the LLM ingests (web pages, e-mails, repository files, output of other MCP servers). The attack does not require a malicious user \u2014 only that the LLM ingests attacker-controlled text at any point during the session.\n\n## Patches\n\nFixed in **1.3.5**.\n\n- Add `--` argument terminator to all `ssh`/`scp` invocations.\n- Strict whitelist for `hostAlias` (rejects leading `-` and shell metacharacters).\n- Known-host check: every `hostAlias` must be defined in `~/.ssh/config` (including `Include` directives) or present in `~/.ssh/known_hosts`.\n- Resolve `ssh.exe`/`scp.exe` to absolute paths and use `shell: false` everywhere on Windows.\n\n## Workarounds\n\nNone. Upgrade to 1.3.5.\n\n## Credit\n\nReported by Pico (@piiiico) as part of an MCP server security audit.",
  "id": "GHSA-p4h8-56qp-hpgv",
  "modified": "2026-04-14T00:04:10Z",
  "published": "2026-04-14T00:04:10Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/AiondaDotCom/mcp-ssh/security/advisories/GHSA-p4h8-56qp-hpgv"
    },
    {
      "type": "WEB",
      "url": "https://github.com/AiondaDotCom/mcp-ssh/issues/9"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/AiondaDotCom/mcp-ssh"
    },
    {
      "type": "WEB",
      "url": "https://github.com/AiondaDotCom/mcp-ssh/releases/tag/1.3.5"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "SSH/SCP option injection allowing local RCE in @aiondadotcom/mcp-ssh"
}