Grades are a hygiene check, not a security guarantee.

MCP, MCP server

Kilntainers

Give Every Agent an Ephemeral Linux Sandb

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.

PERMISSION_DELETE_FILES NETWORK_NO_FIXED_HOST NETWORK_UNNAMED_HOST SECRETS_PATH_DOTENV SECRETS_ENV_READ OBFUSCATION_FILE_OVER_READ_CAP

Why this grade

  • PERMISSION_DELETE_FILES Low

    Contains a call that can delete files.

    src/kilntainers/test_cli_integration.py, line 21 result = subprocess.run(

  • NETWORK_NO_FIXED_HOST Low

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

    src/kilntainers/backends/test_docker_integration.py, line 168 command="curl -s --connect-timeout 2 http://example.com",

  • NETWORK_UNNAMED_HOST Low

    Calls a fixed host that the description does not name.

    src/kilntainers/backends/test_docker_integration.py, line 168 command="curl -s --connect-timeout 2 http://example.com",

  • SECRETS_PATH_DOTENV Low

    Mentions a .env file.

    conftest.py, line 5 # Load .env file before any tests run

  • SECRETS_ENV_READ Note

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

    src/kilntainers/backends/test_e2b_e2e.py, line 25 return os.environ.get("E2B_API_KEY") is not None

  • OBFUSCATION_FILE_OVER_READ_CAP Note

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

    uv.lock, line 1 version = 1

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

    Concern

    can delete files.

    PERMISSION_DELETE_FILES

    src/kilntainers/test_cli_integration.py, line 21

    result = subprocess.run(

    src/kilntainers/test_cli_integration.py, line 77

    result = subprocess.run(

    src/kilntainers/test_cli_integration.py, line 89

    result = subprocess.run(

    Show more

    src/kilntainers/test_cli_integration.py, line 101

    result = subprocess.run(

    src/kilntainers/test_cli_integration.py, line 116

    result = subprocess.run(

    src/kilntainers/test_cli_integration.py, line 130

    result = subprocess.run(

    src/kilntainers/test_cli_integration.py, line 158

    result = subprocess.run(

    src/kilntainers/test_lifecycle_integration.py, line 87

    result = subprocess.run(

    src/kilntainers/backends/test_wasm.py, line 544

    shutil.rmtree(base_dir, ignore_errors=True)

    src/kilntainers/backends/test_wasm.py, line 644

    shutil.rmtree(base_dir, ignore_errors=True)

    src/kilntainers/backends/test_wasm.py, line 691

    shutil.rmtree(base_dir, ignore_errors=True)

    src/kilntainers/backends/test_wasm.py, line 732

    shutil.rmtree(base_dir, ignore_errors=True)

    src/kilntainers/backends/test_wasm.py, line 766

    shutil.rmtree(base_dir, ignore_errors=True)

    src/kilntainers/backends/test_wasm.py, line 792

    shutil.rmtree(base_dir, ignore_errors=True)

    src/kilntainers/backends/wasm.py, line 455

    shutil.rmtree(self._base_dir, ignore_errors=True)

  • Install and update

    Pass

    No install-time script found, and dependencies are pinned or absent.

  • Network

    Concern

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

    NETWORK_NO_FIXED_HOST NETWORK_UNNAMED_HOST

    src/kilntainers/backends/test_docker_integration.py, line 168

    command="curl -s --connect-timeout 2 http://example.com",

    src/kilntainers/backends/test_docker_integration.py, line 184

    command="curl -s --connect-timeout 2 http://example.com",

    src/kilntainers/backends/test_modal_integration.py, line 195

    # Use Python to test network (no curl required)

    Show more

    src/kilntainers/backends/test_modal_integration.py, line 197

    command="python3 -c 'import urllib.request; urllib.request.urlopen(\"http://example.com\", timeout=2)'",

    src/kilntainers/backends/test_modal_integration.py, line 214

    # Use Python to test network (no curl required)

    src/kilntainers/backends/test_modal_integration.py, line 216

    command="python3 -c 'import sys, urllib.request; sys.stdout.write(urllib.request.urlopen(\"http://example.com\", timeout=5).read().decode()[:100])'",

  • Secrets

    Concern

    reads a credential or environment file.

    SECRETS_ENV_READ SECRETS_PATH_DOTENV

    conftest.py, line 5

    # Load .env file before any tests run

    src/kilntainers/backends/test_e2b_e2e.py, line 25

    return os.environ.get("E2B_API_KEY") is not None

    src/kilntainers/backends/test_modal_integration.py, line 28

    if os.getenv("MODAL_TOKEN_ID") and os.getenv("MODAL_TOKEN_SECRET"):

    Show more

    src/kilntainers/backends/test_modal_integration.py, line 109

    if not os.getenv("MODAL_TOKEN_ID") and not os.getenv("MODAL_TOKEN_SECRET"):

    src/kilntainers/backends/test_modal_integration.py, line 116

    original_token_id = os.environ.get("MODAL_TOKEN_ID")

    src/kilntainers/backends/test_modal_integration.py, line 117

    original_token_secret = os.environ.get("MODAL_TOKEN_SECRET")

    .gitignore, line 6

    dist/

  • 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

    uv.lock, line 1

    version = 1

  • 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 79e26f5b93ee. can delete files. can reach example.com. The description does not name that host. can reach a host that is not written as a fixed address. 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: 79e26f5b93ee664435150038b4ee31f01b4e7ec0

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