MCP, MCP server
sandbox
MicroVM sandboxes for AI agents, built on cocoon: a fast-boot guest stack, an in-guest product daemon, a per-node control plane with warm pools, and SDKs for Go and Python.
Compatibility: Not stated.
Grade C
One Medium finding. Read the findings before installing.
Not a guarantee. A hygiene check of the source at the commit shown, not a security audit.
Rescanned at commit f90af50f8083, unchanged since the check below.
PERMISSION_SHELL_UNDECLARED
Why this grade
- PERMISSION_SHELL_UNDECLARED Medium
Runs shell commands that the manifest or description does not mention.
e2e/tls_test.go, line 69
cmd := exec.CommandContext(t.Context(), bin, "run", "--config", configPath)
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
requests shell access. No manifest field names shell or command execution.
PERMISSION_SHELL_UNDECLARED
e2e/tls_test.go, line 69
cmd := exec.CommandContext(t.Context(), bin, "run", "--config", configPath)
e2e/tls_test.go, line 91
cmd := exec.CommandContext(t.Context(), python, "tls_client.py", entry, owner, cert)
mcp/e2e.py, line 18
self.proc = subprocess.Popen(argv, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
Show more
sandboxd/engine/engine.go, line 413
cmd := exec.CommandContext(ctx, e.bin, args...) //nolint:gosec // bin comes from node config, args are built internally
Install and update
Pass
No install-time script found, and dependencies are pinned or absent.
Network
Concern
can reach a host that is not written as a fixed address. can reach 10.255.255.1. The description does not name that host.
NETWORK_NO_FIXED_HOST NETWORK_UNNAMED_HOST
e2e/tls_client.py, line 28
socket.create_connection(proxy.getsockname(), timeout=5) as conn,
e2e/cmd/credsmoke/main.go, line 102
out, _ := plain.Exec(ctx, "sh", "-c", fmt.Sprintf("timeout 4 curl -sSN --noproxy '' -x %s %s 2>&1; true", proxy, sse))
e2e/cmd/credsmoke/main.go, line 260
out, execErr := vault.Exec(ctx, "sh", "-c", fmt.Sprintf("curl -sS -x %s %s", proxy, tt.args))
Show more
e2e/cmd/credsmoke/main.go, line 300
out, err := sb.Exec(ctx, "sh", "-c", fmt.Sprintf("curl -sS -x %s %shttps://%s/headers", proxy, header, echo))
e2e/cmd/credsmoke/main.go, line 313
out, err := sb.Exec(ctx, "sh", "-c", fmt.Sprintf("curl -sSv -o /dev/null -w 'version=%%{http_version}\\n' -x %s https://%s/ 2>&1", proxy, host))
e2e/cmd/credsmoke/main.go, line 328
out, err := sb.Exec(ctx, "sh", "-c", fmt.Sprintf("curl -sS -x %s -H '%s: placeholder' https://%s/headers", proxy, header, echo))
e2e/cmd/egresssmoke/main.go, line 83
out, _ := sb.Exec(ctx, "sh", "-c", fmt.Sprintf("curl -s -m 3 --noproxy '*' %s || echo BLOCKED", target))
e2e/cmd/egresssmoke/main.go, line 97
seen, err := sb.Exec(ctx, "sh", "-c", fmt.Sprintf("curl -s -x %s http://%s/get", proxy, echo))
Secrets
Concern
reads a credential or environment file.
SECRETS_ENV_READ SECRETS_PATH_DOTENV
mcp/main.go, line 30
token := flag.String("token", os.Getenv("SANDBOXD_TOKEN"), "node api token")
sandboxd/egress/secrets.go, line 79
return s.byName[name].env
silkd/src/git.rs, line 76
.env("GIT_COMMITTER_EMAIL", email);
Show more
silkd/src/sysutil.rs, line 111
cmd.env("HOME", pw.dir).env("USER", pw.name);
Agent instructions
Pass
No instruction to ignore earlier instructions or to hide a step.
Obfuscation
Note
the file cap was reached before every file was read.
OBFUSCATION_FILE_CAP_REACHED
sandboxd/types/types_test.go, line 1
package types
Licence
Pass
A licence file is present (LICENSE).
Maintainer activity
Pass
The latest commit is within the last 365 days.
Note
Hygiene check of commit f90af50f8083. requests shell access. No manifest field names shell or command execution. can reach a host that is not written as a fixed address. can reach 10.255.255.1. The description does not name that host. reads a credential or environment file. the file cap was reached before every file was read.
Date and source
Date checked:
github.com
Commit graded: f90af50f808377d1cf5aee6f8eab9b3a98004599
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.