Grades are a hygiene check, not a security guarantee.

MCP, MCP server

Screen Control

Screen Control, an MCP server listed in the PlugVet directory.

Compatibility: Not stated.

Grade B

Minor issues only, no Medium or High. Worth a quick look at the findings below 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 4d5ffe641d42, unchanged since the check below.

INSTALL_UNPINNED NETWORK_NO_FIXED_HOST PERMISSION_SHELL_DECLARED SECRETS_ENV_READ

Why this grade

  • INSTALL_UNPINNED Low

    Dependencies use a range or git URL with no lockfile.

    requirements.txt, line 4 mss>=10.0 # Fast cross-platform screen capture (mss.MSS API)

  • NETWORK_NO_FIXED_HOST Low

    Makes a network call whose host is not written as a fixed address.

    mcp_server.py, line 136 with urllib.request.urlopen(req, timeout=timeout) as resp:

  • PERMISSION_SHELL_DECLARED Note

    Runs shell commands, and the manifest or description says so.

    server.py, line 1033 proc = subprocess.Popen(cmd, stdin=subprocess.DEVNULL,

  • SECRETS_ENV_READ Note

    Reads an environment variable whose name contains KEY, SECRET, TOKEN, PASSWORD or CREDENTIAL.

    mcp_server.py, line 70 tok = os.environ.get("SCREEN_CONTROL_TOKEN")

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.

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

    Note

    requests shell access. The manifest names this permission.

    PERMISSION_SHELL_DECLARED

    server.py, line 1033

    proc = subprocess.Popen(cmd, stdin=subprocess.DEVNULL,

    test-game.py, line 80

    p = subprocess.Popen([exe])

    test-linux.py, line 90

    proc = subprocess.run(args, capture_output=True, text=True, timeout=timeout)

    Show more

    test-linux.py, line 129

    proc = subprocess.Popen(args, stdout=handle, stderr=subprocess.STDOUT,

    backends/linux.py, line 57

    proc = subprocess.run(cmd, capture_output=True, text=True,

    backends/linux.py, line 696

    proc = subprocess.run(

    backends/windows.py, line 666

    result = subprocess.run(

    backends/windows.py, line 681

    result = subprocess.run(

  • Install and update

    Concern

    dependencies are not pinned.

    INSTALL_UNPINNED

    requirements.txt, line 4

    mss>=10.0 # Fast cross-platform screen capture (mss.MSS API)

  • Network

    Concern

    can reach a host that is not written as a fixed address.

    NETWORK_NO_FIXED_HOST

    mcp_server.py, line 136

    with urllib.request.urlopen(req, timeout=timeout) as resp:

    mcp_server.py, line 152

    with urllib.request.urlopen(req, timeout=timeout) as resp:

    test-endtoend.py, line 33

    with urllib.request.urlopen(req, timeout=60) as r:

    Show more

    test-game.py, line 38

    with urllib.request.urlopen(req, timeout=60) as r:

    test-game.py, line 50

    with urllib.request.urlopen(req, timeout=60) as r:

    test-linux.py, line 53

    with urllib.request.urlopen(req, timeout=30) as r:

    test-linux.py, line 65

    with urllib.request.urlopen(req, timeout=30) as r:

    test-linux.py, line 72

    with urllib.request.urlopen(req, timeout=30) as r:

    test-security.py, line 288

    urllib.request.urlopen("http://127.0.0.1:8751/health", timeout=2)

    skills/computer-use/SKILL.md, line 37

    curl -H "$H" "http://127.0.0.1:8745/api/vision/frame?scale=0.5" -o /tmp/f.jpg

    skills/computer-use/SKILL.md, line 40

    curl -X POST http://127.0.0.1:8745/api/key -H "$H" \

    skills/computer-use/SKILL.md, line 45

    curl -H "$H" -o /tmp/check.jpg http://127.0.0.1:8745/api/screenshot

  • Secrets

    Note

    reads an environment variable.

    SECRETS_ENV_READ

    mcp_server.py, line 70

    tok = os.environ.get("SCREEN_CONTROL_TOKEN")

  • Agent instructions

    Pass

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

  • Obfuscation

    Pass

    No encoded or minified payload found.

  • Licence

    Pass

    A licence file is present (LICENSE).

  • Maintainer activity

    Pass

    The latest commit is within the last 365 days.

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Note

Hygiene check of commit 4d5ffe641d42. requests shell access. The manifest names this permission. dependencies are not pinned. can reach a host that is not written as a fixed address. reads an environment variable.

Date and source

Date checked:

View source

github.com

Commit graded: 4d5ffe641d4270c04cb85effc1613d48c1a305f1

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