Kingdom: Time and State
Distributed computation is about time and state. That is, in order for more than one component to communicate, state must be shared, and all that takes time.
Most programmers anthropomorphize their work. They think about one thread of control carrying out the entire program in the same way they would if they had to do the job themselves. Modern computers, however, switch between tasks very quickly, and in multi-core, multi-CPU, or distributed systems, two events may take place at exactly the same time. Defects rush to fill the gap between the programmer's model of how a program executes and what happens in reality. These defects are related to unexpected interactions between threads, processes, time, and information. These interactions happen through shared state: semaphores, variables, the file system, and, basically, anything that can store information.
Race Condition
Abstract
The set callback could lead to a race condition.
Explanation
Node.js allows developers to assign callbacks to IO-blocked events. This allows better performance as the callbacks run asynchronously such that the main application isn't blocked by IO. However, this in turn may lead to race conditions when something outside the callback relies upon code within the callback to be run first.
Example 1: The following code checks a user against a database for authentication.
In this example we're supposed to be calling to a backend database to confirm a user's credentials for login, and if confirmed we set a variable to
Example 1: The following code checks a user against a database for authentication.
...
var authenticated = true;
...
database_connect.query('SELECT * FROM users WHERE name == ? AND password = ? LIMIT 1', userNameFromUser, passwordFromUser, function(err, results){
if (!err && results.length > 0){
authenticated = true;
}else{
authenticated = false;
}
});
if (authenticated){
//do something privileged stuff
authenticatedActions();
}else{
sendUnathenticatedMessage();
}
In this example we're supposed to be calling to a backend database to confirm a user's credentials for login, and if confirmed we set a variable to
true, otherwise false. Unfortunately, since the callback is blocked by IO, it will run asynchronously and may be run after the check to if (authenticated), and since the default was true, it will go into the if-statement whether the user is actually authenticated or not.References
[1] Kristopher Kowal Documentation for q
[2] Piotr Pelczar Asynchronous programming done right.
[3] Standards Mapping - Common Weakness Enumeration CWE ID 362, CWE ID 367
[4] Standards Mapping - Common Weakness Enumeration Top 25 2022 [22] CWE ID 362
[5] Standards Mapping - Common Weakness Enumeration Top 25 2023 [21] CWE ID 362
[6] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-000366, CCI-003178
[7] Standards Mapping - General Data Protection Regulation (GDPR) Indirect Access to Sensitive Data
[8] Standards Mapping - NIST Special Publication 800-53 Revision 4 CM-6 Configuration Settings (P1)
[9] Standards Mapping - NIST Special Publication 800-53 Revision 5 CM-6 Configuration Settings
[10] Standards Mapping - OWASP Application Security Verification Standard 4.0 1.11.2 Business Logic Architectural Requirements (L2 L3), 1.11.3 Business Logic Architectural Requirements (L3), 1.11.2 Business Logic Architectural Requirements (L2 L3), 1.11.3 Business Logic Architectural Requirements (L3), 11.1.6 Business Logic Security Requirements (L2 L3)
[11] Standards Mapping - OWASP Top 10 2021 A04 Insecure Design
[12] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 6.5.6
[13] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.6
[14] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.6
[15] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.6
[16] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0 Requirement 6.2.4
[17] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 4.2 - Critical Asset Protection
[18] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 4.2 - Critical Asset Protection, Control Objective B.3.3 - Terminal Software Attack Mitigation
[19] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 4.2 - Critical Asset Protection, Control Objective B.3.3 - Terminal Software Attack Mitigation
[20] Standards Mapping - SANS Top 25 2009 Insecure Interaction - CWE ID 362
[21] Standards Mapping - SANS Top 25 2010 Insecure Interaction - CWE ID 362
[22] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3630.1 CAT II
[23] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3630.1 CAT II
[24] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3630.1 CAT II
[25] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3630.1 CAT II
[26] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3630.1 CAT II
[27] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3630.1 CAT II
[28] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3630.1 CAT II
[29] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-001995 CAT II
[30] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-001995 CAT II
[31] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-001995 CAT II
[32] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-001995 CAT II
[33] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-001995 CAT II
[34] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-001995 CAT II
[35] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-001995 CAT II
[36] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-001995 CAT II
[37] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-001995 CAT II
[38] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-001995 CAT II
[39] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-001995 CAT II
[40] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-001995 CAT II
[41] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-001995 CAT II
[42] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-001995 CAT II
desc.structural.javascript.race_condition