CWE-413: Improper Resource Locking

Code Examples & CVEs

Demonstrative Examples

The following function attempts to acquire a lock in order to perform operations on a shared resource.

However, the code does not check the value returned by pthread_mutex_lock() for errors. If pthread_mutex_lock() cannot acquire the mutex for any reason, the function may introduce a race condition into the program and result in undefined behavior.

BadC

void f(pthread_mutex_t *mutex) {                         pthread_mutex_lock(mutex);                                                        /* access shared resource */                                                                                    pthread_mutex_unlock(mutex);                      }

The following function attempts to acquire a lock in order to perform operations on a shared resource.

GoodC

int f(pthread_mutex_t *mutex) {                         int result;                            result = pthread_mutex_lock(mutex);if (0 != result)return result;                                                                                    /* access shared resource */                                                                                    return pthread_mutex_unlock(mutex);                      }

This Java example shows a simple BankAccount class with deposit and withdraw methods.

However, the deposit and withdraw methods have shared access to the account balance private class variable. This can result in a race condition if multiple threads attempt to call the deposit and withdraw methods simultaneously where the account balance is modified by one thread before another thread has completed modifying the account balance. For example, if a thread attempts to withdraw funds using the withdraw method before another thread that is depositing funds using the deposit method completes the deposit then there may not be sufficient funds for the withdraw transaction.

BadJava

public class BankAccount {                                                                                 // variable for bank account balance                            private double accountBalance;                                                        // constructor for BankAccount                            public BankAccount() {accountBalance = 0;}                                                        // method to deposit amount into BankAccount                            public void deposit(double depositAmount) {                                                                 double newBalance = accountBalance + depositAmount;accountBalance = newBalance;                            }                                                        // method to withdraw amount from BankAccount                            public void withdraw(double withdrawAmount) {                                                                 double newBalance = accountBalance - withdrawAmount;accountBalance = newBalance;                            }                                                        // other methods for accessing the BankAccount object                            ...                      }

This Java example shows a simple BankAccount class with deposit and withdraw methods.

GoodJava

public class BankAccount {                         ...                            // synchronized method to deposit amount into BankAccount                            public synchronized void deposit(double depositAmount) {...}                                                        // synchronized method to withdraw amount from BankAccount                            public synchronized void withdraw(double withdrawAmount) {...}                            ...                      }

This Java example shows a simple BankAccount class with deposit and withdraw methods.

GoodJava

public class BankAccount {                         ...                            // lock object for thread access to methods                            private ReentrantLock balanceChangeLock;                                                        // condition object to temporarily release lock to other threads                            private Condition sufficientFundsCondition;                                                        // method to deposit amount into BankAccount                            public void deposit(double amount) {                                                                                                   // set lock to block access to BankAccount from other threads                                  balanceChangeLock.lock();try {                                     double newBalance = balance + amount;balance = newBalance;                                                                                // inform other threads that funds are available                                        sufficientFundsCondition.signalAll();                                                                       } catch (Exception e) {...}finally {// unlock lock objectbalanceChangeLock.unlock();}                            }                                                        // method to withdraw amount from bank account                            public void withdraw(double amount) {                                                                                                   // set lock to block access to BankAccount from other threads                                  balanceChangeLock.lock();try {                                     while (balance < amount) {                                                                                                                                       // temporarily unblock access                                                                                                                                          // until sufficient funds are available                                              sufficientFundsCondition.await();                                        }double newBalance = balance - amount;balance = newBalance;                                                                       } catch (Exception e) {...}finally {// unlock lock objectbalanceChangeLock.unlock();}                            }...                      }

Observed CVE Examples (1)

CVE-2022-20141

Chain: an operating system kernel has insufficent resource locking (CWE-413) leading to a use after free (CWE-416).

View Details

Source-backed guidance

Additional facts reviewed against primary or authoritative security sources.

Verify controls for CWE-413 with SSDF evidence

Use NIST SSDF verification and vulnerability-response practices to detect CWE-413, Improper Resource Locking, throughout the product lifecycle. Derive review questions, static or dynamic checks, and negative tests from the CWE's causal behavior; define the components and lifecycle stages each check covers; and retain findings with enough evidence to distinguish the root cause from symptoms and impacts. Track escapes and false negatives, then improve the verification plan after every confirmed occurrence.

NIST SP 800-218 Secure Software Development Framework — National Institute of Standards and Technology

Address Improper Resource Locking during Architecture and Design

MITRE associates mitigation with Architecture and Design, and Implementation; documented detection approaches include Automated Static Analysis; recorded impacts include Modify Application Data, DoS: Instability, and DoS: Crash, Exit, or Restart. Use these source-defined anchors to turn CWE-413 into implementation, review, and verification checks for the affected component.

CWE-413: Improper Resource Locking — MITRE CWE

Triage CWE-413 against known exploitation evidence

Use CISA's Known Exploited Vulnerabilities catalog to test whether a vulnerability mapped to CWE-413, Improper Resource Locking, has evidence of exploitation in the wild. Confirm the CVE-to-CWE root-cause mapping independently before attaching the example, then capture the affected product, required action, and remediation deadline. A missing KEV match is not evidence that the weakness is unexploited, and a KEV entry must not be generalized to every occurrence of this CWE.

Known Exploited Vulnerabilities Catalog — Cybersecurity and Infrastructure Security Agency

Apply precise root-cause mapping to CWE-413

Apply MITRE's full root-cause mapping guidance when using CWE-413, Improper Resource Locking. Separate weakness language from attacker prerequisites and technical impact, check the entry's abstraction and vulnerability-mapping notes, and prefer the most specific Base or Variant supported by the evidence. Record the rejected alternatives and require an independent review before the mapping is used for remediation trends or program metrics.

CVE to CWE Root Cause Mapping Guidance — MITRE CWE

Validate CWE-413 with root-cause mapping checks

Apply MITRE's root-cause mapping quick tips to CWE-413, Improper Resource Locking. Confirm the finding describes the causal weakness rather than an impact or attack pattern, compare the abstraction and mapping notes with plausible alternatives, and have a second reviewer challenge the selection. Preserve the evidence and reasoning so recurring defects can be measured against one consistent identifier.

CVE to CWE Root Cause Mapping Quick Tips — MITRE CWE

Frequently Asked Questions

What is CWE-413: Improper Resource Locking?+

CWE-413: Improper Resource Locking is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The product does not lock or does not correctly lock a resource when the product must have exclusive access to the resource. When a resource is not properly locked, an attacker could modify the resource while it is being operated on by the product. This might violate the product's assumption that the resource will not change, potentially leading to unexpected behaviors.

What are the security consequences of Improper Resource Locking?+

If exploited, CWE-413 (Improper Resource Locking) it can compromise Integrity and Availability, leading to outcomes such as Modify Application Data, DoS: Instability and DoS: Crash, Exit, or Restart.

How do you prevent or mitigate Improper Resource Locking?+

Recommended mitigations for CWE-413 include: Use a non-conflicting privilege scheme. Use synchronization when locking a resource.

Which programming languages are affected by Improper Resource Locking?+

CWE-413 commonly affects Not Language-Specific. Note that weaknesses are often language-agnostic patterns, so secure coding practices apply broadly.

What are real-world examples of Improper Resource Locking?+

MITRE documents real CVEs mapped to CWE-413, including CVE-2022-20141. You can look up the full details of each CVE, including CVSS scores and remediation guidance, on our CVE Lookup tool.

What is the difference between a CWE and a CVE?+

A CWE (Common Weakness Enumeration) like CWE-413 describes a category of software weakness — the underlying flaw type. A CVE (Common Vulnerabilities and Exposures) identifies a specific, real-world vulnerability in a particular product. In short, a CWE is the kind of mistake, and a CVE is an instance of that mistake being found in software.

CWE-413: Improper Resource Locking

Extended Description

Technical Details

Applicable To

Security Consequences

Scope

Impact

Mitigation Strategies

Phase

Description

Phase

Description

Detection Methods

Code Examples & CVEs

Demonstrative Examples

Observed CVE Examples (1)

CWE Relationships

Parent Weaknesses

Source-backed guidance

Verify controls for CWE-413 with SSDF evidence

Address Improper Resource Locking during Architecture and Design

Triage CWE-413 against known exploitation evidence

Apply precise root-cause mapping to CWE-413

Validate CWE-413 with root-cause mapping checks

Frequently Asked Questions

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