What it is: Sensitive Data Storage in Improperly Locked Memory (CWE-591) is a type of vulnerability where sensitive data is stored in memory without proper locking, allowing it to be written to swap files.
Why it matters: This can expose sensitive information to unauthorized access and compromise confidentiality.
How to fix it: Ensure that sensitive data is stored with appropriate locking mechanisms to prevent it from being written to disk.
TL;DR: Sensitive Data Storage in Improperly Locked Memory (CWE-591) occurs when sensitive data is not properly locked in memory, leading to exposure through swap files. Ensure proper protection mechanisms are used.
| Field | Value |
|---|---|
| CWE ID | CWE-591 |
| OWASP Category | Not directly mapped |
| CAPEC | None known |
| Typical Severity | High |
| Affected Technologies | Memory management, virtual memory manager, operating systems |
| Detection Difficulty | Moderate |
| Last Updated | 2026-07-29 |
What is Sensitive Data Storage in Improperly Locked Memory?
Sensitive Data Storage in Improperly Locked Memory (CWE-591) is a type of vulnerability where sensitive data is stored in memory without proper locking mechanisms. This can lead to the data being written to swap files by the virtual memory manager, making it accessible to unauthorized actors.
As defined by the MITRE Corporation under CWE-591, and classified by the OWASP Foundation as not directly mapped, this weakness involves storing sensitive information in improperly locked memory areas.
Quick Summary
Sensitive Data Storage in Improperly Locked Memory occurs when data is stored without proper locking mechanisms, leading to exposure via swap files. This can compromise confidentiality and lead to unauthorized access to sensitive information. Jump to: Overview · Root Cause · Attack Flow · Prerequisites to Exploit · Vulnerable Code · Secure Code · Business Impact · Detection · Fix
Jump to: Quick Summary · Sensitive Data Storage in Improperly Locked Memory Overview · How Sensitive Data Storage in Improperly Locked Memory Works · Business Impact of Sensitive Data Storage in Improperly Locked Memory · Sensitive Data Storage in Improperly Locked Memory Attack Scenario · How to Detect Sensitive Data Storage in Improperly Locked Memory · How to Fix Sensitive Data Storage in Improperly Locked Memory · Framework-Specific Fixes for Sensitive Data Storage in Improperly Locked Memory · How to Ask AI to Check Your Code for Sensitive Data Storage in Improperly Locked Memory · Sensitive Data Storage in Improperly Locked Memory Best Practices Checklist · Sensitive Data Storage in Improperly Locked Memory FAQ · Vulnerabilities Related to Sensitive Data Storage in Improperly Locked Memory · References · Scan Your Own Site
Sensitive Data Storage in Improperly Locked Memory Overview
What: Storing sensitive data without proper locking mechanisms. Why it matters: Exposes sensitive information through swap files, compromising confidentiality and integrity. Where it occurs: Applications that manage sensitive data improperly within memory management frameworks. Who is affected: Systems using virtual memory managers or operating systems with swap file functionality. Who is NOT affected: Systems that do not use swap files or properly lock sensitive data in memory.
How Sensitive Data Storage in Improperly Locked Memory Works
Root Cause
Sensitive data stored without proper locking mechanisms can be written to swap files by the virtual memory manager, exposing it to unauthorized access.
Attack Flow
- An attacker identifies improperly locked sensitive data.
- The data is written to a swap file on disk.
- The attacker gains access to the swap file and reads the sensitive information.
Prerequisites to Exploit
- Sensitive data must be stored without proper locking mechanisms.
- Virtual memory manager must write data to swap files.
Vulnerable Code
def store_sensitive_data(data):
# Store data in memory without proper locking
mem_address = id(data)
This code stores sensitive data without ensuring it is properly locked, allowing the virtual memory manager to write it to a swap file.
Secure Code
def store_sensitive_data_securely(data):
# Ensure data is stored with proper locking mechanisms
mem_address = id(data)
lock_memory(mem_address) # Hypothetical function for locking memory
This code ensures that sensitive data is stored using appropriate locking mechanisms to prevent it from being written to swap files.
Business Impact of Sensitive Data Storage in Improperly Locked Memory
Confidentiality
- Data Exposure: Unauthorized access to sensitive information through swap files.
- Financial Losses: Potential fines and legal costs due to data breaches.
- Reputation Damage: Trust erosion among customers and partners due to compromised data.
Sensitive Data Storage in Improperly Locked Memory Attack Scenario
- An attacker identifies a system storing sensitive data without proper locking mechanisms.
- The virtual memory manager writes the data to swap files on disk.
- The attacker gains access to the swap file and reads the sensitive information, compromising confidentiality.
How to Detect Sensitive Data Storage in Improperly Locked Memory
Manual Testing
- Review code for improper storage of sensitive data without locking mechanisms.
- Check virtual memory manager configurations and settings.
- Verify that sensitive data is stored with appropriate protection measures.
Automated Scanners (SAST/DAST)
Static analysis can identify instances where sensitive data is stored improperly. Dynamic testing can simulate attacks to verify the effectiveness of protective measures.
PenScan Detection
PenScan’s automated scanners like ZAP and Wapiti actively detect improper locking mechanisms for sensitive data storage.
False Positive Guidance
False positives may occur if the system properly locks sensitive data but uses similar patterns in non-sensitive contexts. Ensure that only truly unsecured data is flagged as vulnerable.
How to Fix Sensitive Data Storage in Improperly Locked Memory
- Identify data that needs protection and choose platform-appropriate protection mechanisms.
- Check return values to ensure locking operations are successful.
- Use secure coding practices to prevent improper storage of sensitive data.
- Implement proper memory management techniques to lock sensitive data effectively.
Framework-Specific Fixes for Sensitive Data Storage in Improperly Locked Memory
def store_sensitive_data_securely(data):
# Ensure data is stored with proper locking mechanisms
mem_address = id(data)
lock_memory(mem_address) # Hypothetical function for locking memory
This Python example demonstrates securing sensitive data by ensuring it is properly locked in memory.
How to Ask AI to Check Your Code for Sensitive Data Storage in Improperly Locked Memory
Review the following Python code block for potential CWE-591 Sensitive Data Storage in Improperly Locked Memory vulnerabilities and rewrite it using proper locking mechanisms: [paste code here]
Sensitive Data Storage in Improperly Locked Memory Best Practices Checklist
✅ Identify data that needs protection. ✅ Choose platform-appropriate protection mechanisms. ✅ Check return values to ensure successful locking operations. ✅ Use secure coding practices to prevent improper storage of sensitive data. ✅ Implement proper memory management techniques. ✅ Regularly audit and update security configurations.
Sensitive Data Storage in Improperly Locked Memory FAQ
How does sensitive data storage in improperly locked memory occur?
It occurs when the virtual memory manager writes sensitive data to swap files on disk, making it accessible to external actors.
What is the impact of sensitive data storage in improperly locked memory?
Sensitive data can be exposed and read by unauthorized users, leading to potential breaches and loss of confidential information.
How do I detect sensitive data storage in improperly locked memory vulnerabilities?
Use manual testing techniques like code reviews and automated scanners that check for improper locking mechanisms.
What are the best practices for preventing sensitive data storage in improperly locked memory?
identify data that needs protection and choose appropriate platform-specific protection mechanisms.
How can I fix sensitive data storage in improperly locked memory issues?
Ensure that sensitive data is stored in properly locked memory to prevent it from being written to swap files.
Can you provide an example of vulnerable code for sensitive data storage in improperly locked memory?
Code that stores sensitive information without proper locking mechanisms can be exploited by attackers to access the data on disk.
How does PenScan detect sensitive data storage in improperly locked memory vulnerabilities?
PenScan uses automated scanners like ZAP and Wapiti to identify improper locking of sensitive data.
Vulnerabilities Related to Sensitive Data Storage in Improperly Locked Memory
| CWE | Name | Relationship | |—|—|—| | CWE-413 | Improper Resource Locking (ChildOf) |
References
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 Sensitive Data Storage in Improperly Locked Memory and other risks before an attacker does.