Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
CWE-413 Base Draft
Improper Resource Locking
This vulnerability occurs when an application fails to properly lock a shared resource, such as a file or memory location, before performing operations that require exclusive access.
Definition
What is CWE-413?
This vulnerability occurs when an application fails to properly lock a shared resource, such as a file or memory location, before performing operations that require exclusive access.
Without a proper locking mechanism, concurrent threads or processes can read or modify the same resource simultaneously. This race condition violates the developer's assumption that the resource state is stable during the critical operation, leading to data corruption, crashes, or incorrect application behavior.
Detecting these subtle timing issues in complex, distributed systems is challenging. While SAST tools can flag potential patterns, Plexicus uses AI to analyze runtime context and suggest precise code fixes—like implementing mutexes or semaphores—automating remediation and saving significant manual review time.
Auswirkungen in der Praxis
Real-world CVEs caused by CWE-413
-
Chain: an operating system kernel has insufficent resource locking (CWE-413) leading to a use after free (CWE-416).
Wie Angreifer es ausnutzen
Angreiferpfad Schritt für Schritt
- 1
The following function attempts to acquire a lock in order to perform operations on a shared resource.
- 2
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.
- 3
In order to avoid data races, correctly written programs must check the result of thread synchronization functions and appropriately handle all errors, either by attempting to recover from them or reporting them to higher levels.
- 4
This Java example shows a simple BankAccount class with deposit and withdraw methods.
- 5
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.
Verwundbares Codebeispiel
Vulnerable C
The following function attempts to acquire a lock in order to perform operations on a shared resource.
void f(pthread_mutex_t *mutex) {
pthread_mutex_lock(mutex);
```
/* access shared resource */*
pthread_mutex_unlock(mutex);} Sicheres Codebeispiel
Secure C
In order to avoid data races, correctly written programs must check the result of thread synchronization functions and appropriately handle all errors, either by attempting to recover from them or reporting them to higher levels.
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);} What changed: the unsafe sink is replaced (or the input is validated/escaped) so the same payload no longer triggers the weakness.
Präventions-Checkliste
How to prevent CWE-413
- Architecture and Design Use a non-conflicting privilege scheme.
- Architecture and Design / Implementation Use synchronization when locking a resource.
Erkennungssignale
How to detect CWE-413
CWE-413
Don't catalog this weakness. Prove it's reachable.
Plexicus turns CWE catalogs into evidence: every CWE-pattern is matched against your real code graph, reach is proven on a sandbox clone, and verified findings ship as reviewed PRs.
Häufig gestellte Fragen Was ist CWE-413?
Wie gravierend ist CWE-413?
Welche Sprachen oder Plattformen sind von CWE-413 betroffen?
Wie kann ich CWE-413 verhindern?
Wie erkennt und behebt Plexicus CWE-413?
Wo erfahre ich mehr über CWE-413?
Frequently asked questions
Was ist CWE-413?
This vulnerability occurs when an application fails to properly lock a shared resource, such as a file or memory location, before performing operations that require exclusive access.
Wie gravierend ist CWE-413?
MITRE hat für diese Schwachstelle keine Exploit-Wahrscheinlichkeit veröffentlicht. Behandle sie als mittlere Auswirkung, bis dein Threat Model anderes belegt.
Welche Sprachen oder Plattformen sind von CWE-413 betroffen?
MITRE hat für diese CWE keine betroffenen Plattformen spezifiziert — sie kann in den meisten Anwendungs-Stacks auftreten.
Wie kann ich CWE-413 verhindern?
Use a non-conflicting privilege scheme. Use synchronization when locking a resource.
Wie erkennt und behebt Plexicus CWE-413?
Die SAST-Engine von Plexicus erkennt die Datenfluss-Signatur von CWE-413 bei jedem Commit. Bei einem Treffer öffnet unser Codex-Remedium-Agent einen Fix-PR mit korrigiertem Code, Tests und einer einzeiligen Zusammenfassung für den Reviewer.
Wo erfahre ich mehr über CWE-413?
MITRE veröffentlicht die kanonische Definition unter https://cwe.mitre.org/data/definitions/413.html. Für ergänzende Hinweise kannst du auch die OWASP- und NIST-Dokumentation heranziehen.
Verwandte Schwachstellen
Weaknesses related to CWE-413
CWE-667 Parent
Improper Locking
This vulnerability occurs when a program fails to correctly acquire or release a lock on a shared resource, such as a file, database…
CWE-1232 Sibling
Improper Lock Behavior After Power State Transition
This vulnerability occurs when a hardware lock bit, designed to protect critical system configuration registers, is improperly reset or…
CWE-1233 Sibling
Security-Sensitive Hardware Controls with Missing Lock Bit Protection
This vulnerability occurs when a hardware device uses a lock bit to protect critical configuration registers, but the lock fails to…
CWE-1234 Sibling
Hardware Internal or Debug Modes Allow Override of Locks
Hardware debug modes or internal states can bypass critical system lock protections, allowing unauthorized changes to device configuration.
CWE-412 Sibling
Unrestricted Externally Accessible Lock
This vulnerability occurs when a system correctly checks for a lock's existence, but an unauthorized external actor can control or…
CWE-414 Sibling
Missing Lock Check
This vulnerability occurs when software fails to verify that a proper synchronization lock is active before accessing or modifying a…
CWE-609 Sibling
Double-Checked Locking
Double-checked locking is an insufficient synchronization pattern where a program checks a resource's state, acquires a lock, and checks…
CWE-764 Sibling
Multiple Locks of a Critical Resource
This vulnerability occurs when a critical resource, such as a file, data structure, or connection, is locked more times than the software…
CWE-765 Sibling
Multiple Unlocks of a Critical Resource
This vulnerability occurs when a critical resource, like a lock or semaphore, is unlocked more times than it was locked, putting the…
Ressourcen
Further reading
Bereit, das Wesentliche zu validieren?
Bereit zu validieren, was zählt.
Plexicus ist Proof-Driven AppSec: validierte Funde, kontextuelles Verständnis und geprüfte Remediation — in Evidenz verankert, mit Ihnen gescoped.