SkillTotal

Is calesthio/OpenMontage safe?

No malicious indicators - review capabilities before installing
Notable — review in context (capabilities are not malware):
  • Python shell/command execution
  • Node.js shell/command execution
  • Node.js dynamic code execution

What to do: Nothing here argues against installing it. Grant the capabilities it lists only if you expect the tool to need them.

calesthio/OpenMontage is a PyPI package analyzed by SkillTotal's deterministic static scanner. The scan found no malicious indicators. It can: dynamic code execution, filesystem read, filesystem write, mcp tools detected, network egress and shell execution — capabilities are what the code can do, not a verdict on intent. Risk score 0/100 (low).

repo

python_package · https://github.com/calesthio/OpenMontage
LOW
0
/ 100 risk score
Snapshot · scanned Oct 8, 2026 · repo@9327439 · engine 0.56.4 / ruleset 62

Automated static-analysis result. It can contain false positives and false negatives, and is not a claim about the intent of calesthio/OpenMontage's authors. Report a false positive.

Capabilities — what this component can do (not a risk score):
dynamic code executionfilesystem readfilesystem writemcp tools detectednetwork egressshell execution

Behavioral traits

How this component maps to the CSA agentic threat model. Descriptive — it never affects the risk score.

Tool surface
Tool Usage
Execution authority
Tool Access Control / Direct Tool Access
Filesystem reach
Tool Execution Context
Network egress
Interaction & Communication / Direct Communication

Findings (8)

HIGHNode.js dynamic code executionST-DYN-NODE

The code turns strings into live code at runtime (eval / new Function / exec).

Why it matters: If those strings aren't fixed and trusted, they become a way to run arbitrary code.

Fix: Avoid evaluating dynamically constructed code; if unavoidable, ensure the input is a trusted constant and never derived from external data.

HIGHNode.js shell/command executionST-SHELL-NODE

The component can run operating-system commands or spawn processes.

const result = spawnSync(process.execPath, args, {
import { spawnSync } from "node:child_process";
const result = spawnSync(process.execPath, args, {
import { spawn, spawnSync } from "node:child_process";
return spawnSync("python3", ["-c", probe], { stdio: "ignore" }).status === 0;
return spawnSync("pip", ["install", "-q", ...deps], { stdio: "ignore" }).status === 0;
const proc = spawn("python3", ["-c", script], { detached: true, stdio: ["ignore", fd, fd] });
import { spawn, spawnSync } from "node:child_process";
const r = spawnSync("python3", ["-c", "import elevenlabs"], { stdio: "ignore" });
const p = spawn(cmd, args, { stdio: "ignore", ...opts });
import { execFileSync } from "node:child_process";
import { execFileSync } from "node:child_process";
import { execFileSync } from "node:child_process";
import { execFileSync } from "node:child_process";
import { execFileSync } from "node:child_process";

Why it matters: Powerful and often legitimate — confirm the commands aren't built from untrusted input.

Fix: Confirm the command and its arguments are fully controlled and not derived from untrusted input; prefer execFile with an argument array.

HIGHPython shell/command executionST-SHELL-PY

The component can run operating-system commands or spawn processes.

subprocess.run(["manimgl", __file__, "ThreeDSceneTemplate"])
subprocess.run(["manimgl", __file__, "BasicSceneTemplate"])
subprocess.run(["manimgl", __file__, "MathSceneTemplate"])
subprocess.run(
        ["ffmpeg", "-y", "-i", path, "-ac", "1", "-ar", str(SR), wav],
        capture_output=True, check=True,
    )
return subprocess.run(
        cmd, capture_output=capture, text=True, check=check,
    )
subprocess.check_call(
                    [sys.executable, "-m", "pip", "install", "--quiet", "openai-whisper"]
                )
subprocess.run(["manimgl", __file__, "ThreeDSceneTemplate"])
subprocess.run(["manimgl", __file__, "BasicSceneTemplate"])
subprocess.run(["manimgl", __file__, "MathSceneTemplate"])
return subprocess.run(
        cmd, capture_output=capture, text=True, check=check,
    )
subprocess.check_call(
                    [sys.executable, "-m", "pip", "install", "--quiet", "openai-whisper"]
                )
subprocess.Popen(cmd, **kwargs)
result = subprocess.run(
                ["ffmpeg", "-y", "-loglevel", "error", "-ss", "1.5",
                 "-i", str(source), "-frames:v", "1",
                 "-vf", f"scale={width}:-2", str(tmp)],
                capture_output=True, …
proc = subprocess.run(cmd, capture_output=True, text=True, timeout=30)
proc = subprocess.run(cmd, capture_output=True, text=True, timeout=30)
subprocess.run([npm_cmd, "install"], cwd=COMPOSER_DIR, check=True)
subprocess.run(
        [
            npx_cmd,
            "remotion",
            "render",
            "src/index.tsx",
            "Explainer",
            str(output_path),
            "--props",
            str(props_path), …
subprocess.run(cmd, cwd=COMPOSER_DIR, check=True, capture_output=True, text=True, timeout=600)
subprocess.run(["ffmpeg", "-y", "-loglevel", "error", "-loop", "1",
                    "-i", str(first_frame), "-t", "4", "-vf", "scale=960:540",
                    "-pix_fmt", "yuv420p", str(renders / "final.mp4")],
                   ch …
server = subprocess.Popen(
        [sys.executable, "-m", "backlot", "serve", "--port", str(PORT)],
        env=env, cwd=REPO_ROOT,
        stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
subprocess.run(
                ["npx", "playwright", "screenshot",
                 "--viewport-size", f"{w},{h}",
                 "--wait-for-timeout", str(wait_ms),
                 f"http://127.0.0.1:{PORT}{path}", str(out)], …
subprocess.run(
        [sys.executable, "scripts/backlot_screenshot_stage.py", "--stage-only"],
        cwd=REPO_ROOT,
        check=True,
        timeout=180,
    )
server = subprocess.Popen(
        [sys.executable, "-m", "backlot", "serve", "--port", str(PORT)],
        cwd=REPO_ROOT,
        env=env,
        stdout=subprocess.DEVNULL,
        stderr=subprocess.DEVNULL,
    )
subprocess.run(
        [
            "npx",
            "playwright",
            "screenshot",
            "--viewport-size",
            f"{width},{height}",
            "--wait-for-timeout",
            str(wait_ms),
            url, …

Why it matters: Powerful and often legitimate — confirm the commands aren't built from untrusted input.

Fix: Confirm the command and its arguments are fully controlled and not derived from untrusted input; avoid shell=True.

MEDIUMPython filesystem readST-FS-PY-READ

The component reads files from disk.

with open(os.path.join(tmp_dir, json_files[0]), "r") as f:
with open(os.path.join(tmp_dir, json_files[0]), "r") as f:
html = (UI_DIR / name).read_text(encoding="utf-8")
with open(path, encoding="utf-8", errors="replace") as f:
with open(CHECKPOINT_SCHEMA_PATH, encoding="utf-8") as f:
with open(marker_path, encoding="utf-8") as f:
with open(path, encoding="utf-8") as handle:
with open(path, encoding="utf-8") as f:
with open(path, encoding="utf-8") as f:
with open(marker_path, encoding="utf-8") as f:
with open(path, encoding="utf-8") as f:
with open(checkpoints[0], encoding="utf-8") as f:
with open(config_path) as f:
with open(self.index_path, encoding="utf-8") as f:
with open(path, encoding="utf-8", errors="replace") as f:
with open(SCHEMA_PATH, encoding="utf-8") as f:
with open(path, encoding="utf-8") as f:
with open(PLAYBOOK_SCHEMA_PATH) as f:
with open(path, encoding="utf-8") as f:
return json.loads(path.read_text(encoding="utf-8"))
previous = json.loads(manifest_path.read_text(encoding="utf-8"))
manifest = json.loads(manifest_path.read_text(encoding="utf-8"))
with open(SCHEMA_PATH, encoding="utf-8") as f:

Why it matters: Usually legitimate, but worth confirming it can't be steered into reading sensitive files.

Fix: Confirm which files are read and that paths cannot be influenced by untrusted input to reach sensitive locations.

MEDIUMPython filesystem write/deleteST-FS-PY-WRITE

The component writes or deletes files on disk.

Path(a.out).write_text(json.dumps(d, ensure_ascii=False, indent=2))
with open(args.output, "w", encoding="utf-8") as f:
with open(args.output, "w", encoding="utf-8") as f:
with open(marker_path, "w", encoding="utf-8") as f:
shutil.copyfile(path, target)
with open(path, "w", encoding="utf-8") as f:
with open(tmp_path, "w", encoding="utf-8") as f:
with open(tmp_index, "w", encoding="utf-8") as f:
with open(path, "a", encoding="utf-8") as f:
with open(path, "w") as f:
manifest_path.write_text(json.dumps(manifest, indent=2), encoding="utf-8")
(art_dir / "decision_log.json").write_text(json.dumps(decision_log(pid), indent=2))
(art_dir / "script.json").write_text(json.dumps(script, indent=2))
(art_dir / "scene_plan.json").write_text(json.dumps(plan, indent=2))
(art_dir / "asset_manifest.json").write_text(json.dumps(manifest, indent=2))
(art_dir / "edit_decisions.json").write_text(json.dumps(edit, indent=2))

Why it matters: Usually legitimate, but worth confirming the paths can't be controlled by untrusted input.

Fix: Confirm which files are written/deleted and that paths cannot be influenced by untrusted input.

MEDIUMNode.js network egressST-NET-NODE

The component makes outbound network requests.

const res = await fetch(`${HEYGEN_BASE}${path}`, opts);
fetch("https://cdn.jsdelivr.net/npm/world-atlas@2.0.2/countries-110m.json").then(function(r){return r.json();}).then(function(w){
const res = await fetch(url);
const r = await fetch(url); if (!r.ok) throw new Error(`fetch failed ${r.status}: ${url}`);

Why it matters: Usually legitimate, but confirm the destinations are expected and no sensitive data leaves.

Fix: Confirm the destination hosts are expected and that no sensitive data is sent off-host.

MEDIUMPython network egressST-NET-PY

The component makes outbound network requests.

response = requests.request(
                    method,
                    url,
                    headers=self.headers,
                    timeout=30,
                    **kwargs,
                )
response = requests.request(
                    method,
                    url,
                    headers=self.headers,
                    timeout=30,
                    **kwargs,
                )
import urllib.request
with urllib.request.urlopen(f"http://127.0.0.1:{port}/api/health", timeout=1.5) as resp:
with urllib.request.urlopen(f"http://127.0.0.1:{PORT}/api/health", timeout=1):
with urllib.request.urlopen(f"http://127.0.0.1:{PORT}/api/health", timeout=1):
with urllib.request.urlopen(f"{base_url.rstrip('/')}{path}", timeout=10) as response:
resp = requests.get(f"{self.server_url}/system_stats", timeout=5)
resp = requests.get(
                    f"{self.server_url}/object_info/{node_class}", timeout=10
                )
response = requests.get(
                f"{self.server_url}/object_info/{node_class}", timeout=10
            )
resp = requests.post(
            f"{self.server_url}/prompt",
            json={"prompt": workflow, "client_id": self.client_id},
            timeout=30,
        )
resp = requests.get(f"{self.server_url}/history/{prompt_id}", timeout=10)
resp = requests.get(
            f"{self.server_url}/view",
            params={
                "filename": filename,
                "subfolder": subfolder,
                "type": folder_type,
            },
            timeout=120, …
resp = requests.post(
                f"{self.server_url}/upload/image",
                files={"image": (name, f, "image/png")},
                timeout=30,
            )
self.session = session or requests.Session()

Why it matters: Usually legitimate, but confirm the destinations are expected and no sensitive data leaves.

Fix: Confirm the destination hosts are expected and that no sensitive data is sent off-host.

LOWMCP tool surface detectedST-MCP-DETECTED

An MCP tool surface (manifest or tool definitions) was found.

Why it matters: Just context — review which tools it offers and their permissions.

Fix: Review the declared MCP tools and their permissions.

How attackers abuse these capabilities

Interactive labs on the attack class behind the rules above. They show the technique, not anything found in calesthio/OpenMontage.

Check your own component

Run the same evidence-backed scan on any MCP server, agent skill, or package.

Scan your own component

How we determine this: deterministic static analysis (regex + AST), evidence-anchored, no code execution. Methodology →