What is Insecure Preserved Inherited Permissions (CWE-278)?

TL;DR: Insecure Preserved Inherited Permissions (CWE-278) is a critical security misconfiguration that allows insecure permissions to be preserved during file operations. Properly managing trust zones and privilege separation can prevent this vulnerability.

What is Insecure Preserved Inherited Permissions?

Insecure Preserved Inherited Permissions (CWE-278) is a type of security misconfiguration vulnerability where insecure permissions are preserved during file operations without user awareness or involvement. As defined by the MITRE Corporation under CWE-278, and classified by the OWASP Foundation as not directly mapped to any specific category.

Quick Summary

Insecure Preserved Inherited Permissions can lead to unauthorized access and modification of sensitive data, compromising system integrity and confidentiality. It is critical for developers to manage trust zones and privilege separation during file operations to prevent this vulnerability. Jump to: Overview · How it Works · Business Impact · Attack Scenario · Detection · Fixing · Framework-Specific Fixes · Ask AI · Best Practices Checklist · FAQ

Jump to: Quick Summary · Insecure Preserved Inherited Permissions Overview · How Insecure Preserved Inherited Permissions Works · Business Impact of Insecure Preserved Inherited Permissions · Insecure Preserved Inherited Permissions Attack Scenario · How to Detect Insecure Preserved Inherited Permissions · How to Fix Insecure Preserved Inherited Permissions · Framework-Specific Fixes for Insecure Preserved Inherited Permissions · How to Ask AI to Check Your Code for Insecure Preserved Inherited Permissions · Insecure Preserved Inherited Permissions Best Practices Checklist · Insecure Preserved Inherited Permissions FAQ · Vulnerabilities Related to Insecure Preserved Inherited Permissions · References · Scan Your Own Site

Insecure Preserved Inherited Permissions Overview

What: Insecure Preserved Inherited Permissions is a security misconfiguration where insecure permissions are preserved during file operations without user awareness or involvement.

Why it matters: This vulnerability can lead to unauthorized access and modification of sensitive data, compromising system integrity and confidentiality.

Where it occurs: During file copying or archiving processes in applications that handle file systems and access control mechanisms.

Who is affected: Applications that perform file operations without proper privilege management and trust zone compartmentalization.

Who is NOT affected: Systems already using robust privilege separation functionality and explicit permission management during file operations.

How Insecure Preserved Inherited Permissions Works

Root Cause

The root cause of this vulnerability lies in the lack of proper privilege management and trust zone compartmentalization during file operations. When insecure permissions are preserved without user awareness, sensitive data can be accessed or modified by unauthorized users.

Attack Flow

1. An attacker identifies a file operation that copies files from a directory with insecure permissions.
2. The attacker exploits this vulnerability to copy the files to another location while preserving the insecure permissions.
3. Unauthorized access and modification of sensitive data occur as a result.

Prerequisites to Exploit

• Insecure permissions are present in the source directory.
• File operations that preserve these permissions without user intervention or awareness.

Vulnerable Code

import shutil

def copy_files(src, dest):
    shutil.copytree(src, dest)

This code snippet demonstrates a scenario where insecure permissions from the src directory are preserved during copying to the dest directory without proper privilege management.

Secure Code

import os
import shutil

def copy_files_securely(src, dest):
    # Ensure secure permission handling
    for root, dirs, files in os.walk(src):
        for dir_path in [root] + dirs:
            shutil.copytree(dir_path, os.path.join(dest, os.path.relpath(dir_path, src)), 
                            ignore_dangling_symlinks=True)

This code ensures that proper privilege management and trust zone compartmentalization are enforced during file operations to prevent insecure permissions from being preserved.

Business Impact of Insecure Preserved Inherited Permissions

Confidentiality: Sensitive data can be accessed by unauthorized users, leading to potential data breaches. Integrity: Unauthorized modification of application data compromises system integrity. Availability: None directly impacted in this scenario.

• Financial loss due to data breaches
• Compliance issues and regulatory fines
• Damage to reputation and customer trust

Insecure Preserved Inherited Permissions Attack Scenario

1. An attacker identifies a file operation that copies files from a directory with insecure permissions.
2. The attacker exploits this vulnerability by copying the files to another location while preserving the insecure permissions.
3. Unauthorized access and modification of sensitive data occur as a result.

How to Detect Insecure Preserved Inherited Permissions

Manual Testing

• Review file operations for any instances where insecure permissions are preserved during copying or archiving processes.
• Ensure that proper privilege management is enforced during these operations.

Automated Scanners (SAST / DAST)

Static analysis can identify code patterns where insecure permissions are preserved without user intervention. Dynamic testing may be required to confirm the actual impact in a runtime environment.

PenScan Detection

PenScan’s scanner engines such as ZAP, Nuclei, Wapiti, Nikto, SSLyze, and Dalfox can detect instances of Insecure Preserved Inherited Permissions during automated scans.

False Positive Guidance

A false positive may occur if the pattern looks risky but is actually safe due to context a scanner cannot see. Ensure that the code performs proper privilege management before considering it as a true vulnerability.

How to Fix Insecure Preserved Inherited Permissions

• Very carefully manage the setting, management, and handling of privileges.
• Explicitly manage trust zones in the software to prevent insecure permissions from being preserved during file operations.

Framework-Specific Fixes for Insecure Preserved Inherited Permissions

Python

import os
import shutil

def copy_files_securely(src, dest):
    # Ensure secure permission handling
    for root, dirs, files in os.walk(src):
        for dir_path in [root] + dirs:
            shutil.copytree(dir_path, os.path.join(dest, os.path.relpath(dir_path, src)), 
                            ignore_dangling_symlinks=True)

How to Ask AI to Check Your Code for Insecure Preserved Inherited Permissions

Insecure Preserved Inherited Permissions Best Practices Checklist

✅ Carefully manage the setting, management, and handling of privileges during file operations. ✅ Ensure that appropriate compartmentalization is built into the system design to reinforce privilege separation functionality. ✅ Use the principle of least privilege to decide the appropriate time to use privileges and drop them when necessary.

Insecure Preserved Inherited Permissions FAQ

How does Insecure Preserved Inherited Permissions work?

It occurs when a product inherits insecure permissions from an object, such as during file copying or archiving, without user awareness or involvement.

Why is it important to prevent Insecure Preserved Inherited Permissions?

Preventing this vulnerability ensures that sensitive data remains confidential and secure by managing privileges carefully.

Can you provide a real-world example of Insecure Preserved Inherited Permissions?

An example would be when an application copies files from a directory with insecure permissions to another location, preserving those permissions without user intervention.

How do I detect Insecure Preserved Inherited Permissions in my code?

Manually review file operations and permission handling for any instances where insecure permissions are preserved during copying or archiving processes.

What is the impact of Insecure Preserved Inherited Permissions on system integrity?

It allows unauthorized modification of application data, compromising system integrity.

How can I fix Insecure Preserved Inherited Permissions in my code?

Explicitly manage trust zones and ensure that privileges are dropped when necessary to prevent insecure permissions from being preserved.

What is the best practice for preventing Insecure Preserved Inherited Permissions in Python applications?

Use secure coding practices such as compartmentalizing systems and ensuring privilege separation during file operations.

Vulnerabilities Related to Insecure Preserved Inherited Permissions

References

• MITRE: CWE-278
• [NVD: https://nvd.nist.gov/]

Scan Your Own Site

Manual code review catches what you know to look for. An automated scan catches what you didn’t. Scan your own website using PenScan to find Insecure Preserved Inherited Permissions and other risks before an attacker does.