SkillTotal

Is transformers safe?

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

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

transformers is a PyPI package analyzed by SkillTotal's deterministic static scanner. The scan found no malicious indicators, though 1 risky construct is reported for review. It can: dynamic code execution, filesystem read, filesystem write, install time execution, network egress and shell execution — capabilities are what the code can do, not a verdict on intent. Risk score 20/100 (low).

transformers-5.19.0 5.19.0

python_package · pypi:transformers
LOW
20
/ 100 risk score
Snapshot · scanned Oct 8, 2026 · transformers-5.19.0@5.19.0 · 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 transformers's authors. Report a false positive.

Capabilities — what this component can do (not a risk score):
dynamic code executionfilesystem readfilesystem writeinstall time executionnetwork egressshell execution

Behavioral traits

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

Execution authority
Tool Access Control / Direct Tool Access
Filesystem reach
Tool Execution Context
Network egress
Interaction & Communication / Direct Communication
Supply-chain provenance risk
General Protections / Supply Chain
Unsafe deserialization
General Protections / Input Validation

Findings (7)

HIGHUnsafe deserializationST-DESERIALIZE-PY

It loads data with a format that can rebuild arbitrary objects (e.g. pickle, or unsafe YAML).

self.index_id_to_db_id = pickle.load(metadata_file)

Why it matters: Feeding such a loader untrusted data can execute code hidden inside that data.

Fix: Deserialize untrusted data with a safe format/loader: JSON, or yaml.safe_load / Loader=SafeLoader. Reserve pickle/marshal for data you fully control.

HIGHPython dynamic code executionST-DYN-PY

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

wrapped_encoder = Seq2SeqLMEncoderExportableModule(self.encoder).to(self.full_model.device).eval()
Seq2SeqLMDecoderExportableModuleWithStaticCache(
                model=self.full_model,
                max_static_cache_length=self.generation_config.cache_config.get("max_cache_len"),
                batch_size=self.generation_config.cach …
self.semantic_model = AutoModel.from_config(config.semantic_model_config).eval()
self.semantic_model = AutoModel.from_config(config.semantic_model_config).eval()

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.

HIGHPython install/build-time execution hookST-INSTALL-PY

The Python build/install configuration runs code at install time.

cmdclass={"deps_table_update": DepsTableUpdateCommand},

Why it matters: Code that runs during pip install is a common supply-chain execution point.

Fix: Verify the build hook performs only a legitimate build step and does not execute commands or reach the network during installation.

HIGHPython shell/command executionST-SHELL-PY

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

subprocess.run(
        ["ruff", "check", new_module_folder, tests_folder, model_init_file, "--fix"],
        cwd=repo_path,
        stdout=subprocess.DEVNULL,
    )
subprocess.run(
        ["ruff", "format", new_module_folder, tests_folder, model_init_file],
        cwd=repo_path,
        stdout=subprocess.DEVNULL,
    )
subprocess.run(
        ["python", "utils/check_doc_toc.py", "--fix_and_overwrite"], cwd=repo_path, stdout=subprocess.DEVNULL
    )
subprocess.run(["python", "utils/sort_auto_mappings.py"], cwd=repo_path, stdout=subprocess.DEVNULL)
subprocess.run(
        ["python", "utils/modular_model_converter.py", new_lowercase_name], cwd=repo_path, stdout=subprocess.DEVNULL
    )
ffmpeg_process = subprocess.Popen(ffmpeg_command, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
with subprocess.Popen(ffmpeg_command, stdin=subprocess.PIPE, stdout=subprocess.PIPE) as ffmpeg_process:
with subprocess.Popen(ffmpeg_command, stdout=subprocess.PIPE, bufsize=bufsize) as ffmpeg_process:
ffmpeg_devices = subprocess.run(command, text=True, stderr=subprocess.PIPE, encoding="utf-8")
subprocess.check_output(["ninja", "--version"])

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.

long_description=open("README.md", "r", encoding="utf-8").read(),
with open(audio, "rb") as audio_file:
with open(file_name, "r", encoding="utf-8") as f:
autofile = (repo_path / "src" / "transformers" / "models" / "auto" / "auto_mappings.py").read_text()
file = (repo_path / "src" / "transformers" / "models" / "auto" / filename).read_text()
with open(toc_file, "r", encoding="utf-8") as f:
with open(module_name, "r", encoding="utf-8") as file:
with open(original_test_path, "r", encoding="utf-8") as f:
with open(examples_path, encoding="utf-8") as f:
with open(json_file, encoding="utf-8") as reader:
with open(self.original_tokenizer.vocab_file, "rb") as f:
with open(
            os.path.join(data_dir, self.train_file if filename is None else filename), "r", encoding="utf-8"
        ) as reader:
with open(
            os.path.join(data_dir, self.dev_file if filename is None else filename), "r", encoding="utf-8"
        ) as reader:
with open(input_file, "r", encoding="utf-8-sig") as f:
with open(module_file, encoding="utf-8") as f:
with open(filename, encoding="utf-8") as f:
module_hash: str = hashlib.sha256(b"".join(bytes(f) + f.read_bytes() for f in module_files)).hexdigest()
source_files_hash.update(file_path.read_bytes())
with open(requirements, "r", encoding="utf-8") as f:
with open(json_path, encoding="utf-8") as f:
with open(json_file, encoding="utf-8") as reader:

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.

shutil.rmtree(stale_egg_info)
with open(target, "w", encoding="utf-8", newline="\n") as f:
with open(file_name, "w", encoding="utf-8") as f:
with open(new_module_folder / f"modular_{new_lowercase_name}.py", "w", encoding="utf-8") as f:
with open(new_module_folder / "__init__.py", "w", encoding="utf-8") as f:
with open(tests_folder / "__init__.py", "w", encoding="utf-8"):
with open(tests_folder / filename, "w", encoding="utf-8") as f:
with open(
        repo_path / "docs" / "source" / "en" / "model_doc" / f"{new_lowercase_name}.md", "w", encoding="utf-8"
    ) as f:
with open(filename, "w", encoding="utf-8") as f:
with open(json_file_path, "w", encoding="utf-8") as writer:
with open(output_prediction_file, "w", encoding="utf-8") as writer:
with open(output_nbest_file, "w", encoding="utf-8") as writer:
with open(output_null_log_odds_file, "w", encoding="utf-8") as writer:
with open(output_prediction_file, "w", encoding="utf-8") as writer:
with open(output_nbest_file, "w", encoding="utf-8") as writer:
with open(output_null_log_odds_file, "w", encoding="utf-8") as writer:
with open(json_file_path, "w", encoding="utf-8") as f:
shutil.copyfile(resolved_module_file, submodule_path / module_file)
shutil.copyfile(source_file, target_path)
shutil.copyfile(resolved_module_file, submodule_path / module_file)
shutil.copyfile(object_file, dest_file)
shutil.copyfile(needed_file, dest_file)
with open(json_path, "w", encoding="utf-8") as f:
with open(json_file_path, "w", encoding="utf-8") as writer:

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.

MEDIUMPython network egressST-NET-PY

The component makes outbound network requests.

response = requests.post(
            urljoin(get_service_root_url(self.base_url) + "/", "load_model"), json={"model": model}, stream=True
        )
from .requests import RequestState, RequestStatus
from .requests import RequestState, RequestStatus, get_device_and_memory_breakdown, logger
logger.info(f"Paged cache initialized: {self.max_batch_tokens = }, {self.num_sectors = }, {mb_per_sector = }")
logger.debug(f"Found a prefix match of {prefix_len} tokens for request {request_id}")
logger.debug(f"Evicting {len(evicted_blocks)} cached blocks from allocator {allocator.index}")
_, total, reserved, allocated = get_device_and_memory_breakdown()
logger.info(f"Memory available for cache allocation: {available_memory // 1024**2} MB")
logger.warning(f"Processor {class_name} might not be supported by CB.")
logger.warning(f"Processor {class_name} isn't supported by CB. Dropping it.")
logger.warning(f"Processor {class_name} isn't supported by CB. Kept it because {drop_unsupported = }.")
logger.warning(
            f"Ignored logit_processor_kwargs: {problematic_keys}. {self.supported_keys = } and {self.ignored_keys = }"
        )
from .requests import GenerationOutput, RequestState, RequestStatus, logger
logger.info(
            f"Rank {global_rank} requested background thread to stop with {status = }. Now {self._local_status = }"
        )
logger.error(f"A fatal error was already recorded, ignoring later error: {error}")
logger.error(f"Error processing new request: {e}", exc_info=True)
logger.warning(
                    f"{msg} Switching from {original_attn_impl} to {target_implem}. If you need to use eager or sdpa, "
                    "set `auto_switch_to_flash=False` in the continuous batching config." …
logger.info(f"{msg} Consider using a flash `attn_implementation` when loading the model.")
logger.warning("Manager thread is already running.")
logger.warning("\nBatch processor was not initialized.")
logger.info("Continuous batching manager will be kept for next session.")
logger.warning(f"Generation thread did not exit after join timeout ({timeout}).")

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.

How attackers abuse these capabilities

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

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