Grades are a hygiene check, not a security guarantee.

MCP, MCP server

Mail Mcp

mail-mcp Production-ready email MCP server for AI agents IMAP + SMTP + EWS + Microsoft Graph API — built in Rust

Compatibility: Not stated.

Grade C

One Medium finding. Read the findings before installing.

Graded by PlugVetRubric v2

Not a guarantee. A hygiene check of the source at the commit shown, not a security audit.

Rescanned at commit a6ac703b539b.

INSTALL_REMOTE_SCRIPT

Why this grade

  • INSTALL_REMOTE_SCRIPT Medium

    Fetches a script from the network and runs it (a pipe to a shell, or an install hook with a URL).

    .github/workflows/release.yml, line 77 run: "curl --proto '=https' --tlsv1.2 -LsSf https://github.com/axodotdev/cargo-dist/releases/download/v0.31.0/cargo-dist-installer.sh | sh"

Any High, or two or more Medium findings, give D. One Medium gives C. Low findings or a security Note give B. Each code names a finding behind the letter.

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Grades are a hygiene check of the source at the commit shown, on the date checked, not a security audit or a guarantee. The free directory grades are automated. Before release, a PlugVet engineer reviews every paid report and any grade we hold back, including all F grades, against the source code and the evidence we quote.

What was checked

Plain notes from the hygiene checks.

  • Permissions

    Pass

    No shell or command execution found, and no extra permission was declared.

  • Install and update

    Serious

    install fetches a script from the network. The docs document an installer that pipes a download into a shell.

    INSTALL_REMOTE_SCRIPT INSTALL_DOCUMENTED_INSTALLER

    .github/workflows/release.yml, line 77

    run: "curl --proto '=https' --tlsv1.2 -LsSf https://github.com/axodotdev/cargo-dist/releases/download/v0.31.0/cargo-dist-installer.sh | sh"

    .github/workflows/release.yml, line 137

    curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y

    site/index.html, line 229

    <pre><code>curl --proto '=https' --tlsv1.2 -LsSf https://github.com/tecnologicachile/mail-mcp/releases/latest/download/mail-mcp-installer.sh | sh</code></pre>

    Show more

    README.md, line 472

    curl --proto '=https' --tlsv1.2 -LsSf https://github.com/tecnologicachile/mail-mcp/releases/latest/download/mail-mcp-installer.sh | sh

    site/llms-full.txt, line 47

    curl --proto '=https' --tlsv1.2 -LsSf https://github.com/tecnologicachile/mail-mcp/releases/latest/download/mail-mcp-installer.sh | sh

    site/llms.txt, line 7

    Install: `brew install tecnologicachile/tap/mail-mcp` (macOS/Linux), `curl --proto '=https' --tlsv1.2 -LsSf https://github.com/tecnologicachile/mail-mcp/releases/latest/download/ma

  • Network

    Concern

    can reach a host that is not written as a fixed address. can reach login.microsoftonline.com. The description does not name that host.

    NETWORK_NO_FIXED_HOST NETWORK_UNNAMED_HOST

    scripts/test-greenmail-mcp-inspector.sh, line 43

    with socket.create_connection((host, port), timeout=1.5):

    scripts/test-greenmail.sh, line 28

    with socket.create_connection((host, port), timeout=1.5) as sock:

    src/models.rs, line 330

    /// MIME part id to fetch (e.g. `1.2`), as shown by `imap_get_message`.

    Show more

    src/models.rs, line 333

    /// Attachment filename to fetch (case-insensitive). Used when `part_id`

    docs/account-setup.md, line 273

    data = requests.post('https://login.microsoftonline.com/common/oauth2/v2.0/devicecode',

    docs/account-setup.md, line 279

    td = requests.post('https://login.microsoftonline.com/common/oauth2/v2.0/token',

    src/server.rs, line 1031

    "script": "python3 -c \"\nimport requests, time\nclient_id = '9e5f94bc-e8a4-4e73-b8be-63364c29d753'\nscope = 'https://graph.microsoft.com/Mail.Send offline_access'\ndata = requests

  • Secrets

    Concern

    reads a credential or environment file.

    SECRETS_PATH_DOTENV

    scripts/run-mcp.sh, line 7

    # The server calls dotenvy::dotenv(), which loads `.env` from the process

    scripts/run-mcp.sh, line 9

    # not the repo root, so `.env` is never found and accounts fail to load.

    scripts/run-mcp.sh, line 16

    # 3. Require a .env file at the repo root (copy from .env.example)

    Show more

    scripts/run-mcp.sh, line 22

    # cp -n .env.example .env # then fill credentials

    scripts/run-mcp.sh, line 27

    # a local .env file.

    scripts/run-mcp.sh, line 44

    if [[ ! -f "$ROOT/.env" ]]; then

    scripts/run-mcp.sh, line 45

    echo "mail-mcp: missing $ROOT/.env (copy from .env.example and fill credentials)" >&2

  • Agent instructions

    Pass

    No instruction to ignore earlier instructions or to hide a step.

  • Obfuscation

    Note

    a file was over the read cap and was not fully read.

    OBFUSCATION_FILE_OVER_READ_CAP

    src/server.rs, line 1

    //! MCP server implementation with tool handlers

  • Licence

    Pass

    A licence file is present (LICENSE).

  • Maintainer activity

    Pass

    The latest commit is within the last 365 days.

Get the full report on this tool, £49

Note

Hygiene check of commit a6ac703b539b. install fetches a script from the network. can reach a host that is not written as a fixed address. can reach login.microsoftonline.com. The description does not name that host. reads a credential or environment file. a file was over the read cap and was not fully read.

Date and source

Date checked:

View source

github.com

Commit graded: a6ac703b539b3cf69a79768709dfcbe82a6f6d61

This link goes to the original host. PlugVet does not host or check what you download from there, and installing it is your own decision and risk.

Read how this letter is chosen