Kingdom: Security Features

Software security is not security software. Here we're concerned with topics like authentication, access control, confidentiality, cryptography, and privilege management.

Biometric Authentication: Insecure Touch ID Implementation

Objective-C
Swift

Abstract

The application uses the LocalAuthentication framework to authenticate the user which may not be sufficient for apps requiring heightened security controls.

Explanation

Touch ID based authentication can be implemented in two different flavors: using the LocalAuthentication framework or using Touch ID based access controls in the Keychain service.

Although both of them should be strong enough for most applications, the LocalAuthentication approach has some characteristics that make it less suitable for high risk apps such as banking, medical, and insurance:

- LocalAuthentication is defined outside of the device's Secure Enclave which implies that their APIs can be hooked and modified on jailbroken devices.
- LocalAuthentication authenticates the user by evaluating the context policy which may only evaluate to true or false. This boolean evaluation implies that the application will not be able to know who is really being authenticated, it just knows that fingerprint that is registered with the device was used or not. In addition, fingerprints that could be registered in the future will also successfully evaluate to true.

Example 1: The following code uses the LocalAuthentication framework to perform user authentication:


    ...
    LAContext *context = [[LAContext alloc] init];  
    NSError *error = nil;  
    NSString *reason = @"Please authenticate using the Touch ID sensor.";
    
    if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {  
        [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics
            localizedReason:reason
                reply:^(BOOL success, NSError *error) {
                    if (success) {
                        // Fingerprint was authenticated
                    } else {
                        // Fingerprint could not be authenticated
                    }
            }
        ];
    ...

References

[1] David Thiel iOS Application Security: The Definitive Guide for Hackers and Developers No Starch Press

[2] Integrating Touch ID Into Your iOS Applications Cigital

[3] Don't Touch Me That Way nVisium

[4] SecAccessControlCreateFlags Apple

[5] Standards Mapping - Common Weakness Enumeration CWE ID 287

[6] Standards Mapping - Common Weakness Enumeration Top 25 2019 [13] CWE ID 287

[7] Standards Mapping - Common Weakness Enumeration Top 25 2020 [14] CWE ID 287

[8] Standards Mapping - Common Weakness Enumeration Top 25 2021 [14] CWE ID 287

[9] Standards Mapping - Common Weakness Enumeration Top 25 2022 [14] CWE ID 287

[10] Standards Mapping - Common Weakness Enumeration Top 25 2023 [13] CWE ID 287

[11] Standards Mapping - Common Weakness Enumeration Top 25 2024 [14] CWE ID 287

[12] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-001958

[13] Standards Mapping - FIPS200 CM, SC

[14] Standards Mapping - General Data Protection Regulation (GDPR) Access Violation

[15] Standards Mapping - NIST Special Publication 800-53 Revision 4 IA-3 Device Identification and Authentication (P1)

[16] Standards Mapping - NIST Special Publication 800-53 Revision 5 IA-3 Device Identification and Authentication

[17] Standards Mapping - OWASP Application Security Verification Standard 4.0 2.7.1 Out of Band Verifier Requirements (L1 L2 L3), 2.7.2 Out of Band Verifier Requirements (L1 L2 L3), 2.7.3 Out of Band Verifier Requirements (L1 L2 L3), 2.8.4 Single or Multi Factor One Time Verifier Requirements (L2 L3), 2.8.5 Single or Multi Factor One Time Verifier Requirements (L2 L3), 3.7.1 Defenses Against Session Management Exploits (L1 L2 L3), 9.2.3 Server Communications Security Requirements (L2 L3)

[18] Standards Mapping - OWASP Mobile 2014 M5 Poor Authorization and Authentication

[19] Standards Mapping - OWASP Mobile 2024 M3 Insecure Authentication/Authorization

[20] Standards Mapping - OWASP Mobile Application Security Verification Standard 2.0 MASVS-AUTH-1, MASVS-AUTH-2

[21] Standards Mapping - OWASP Top 10 2004 A10 Insecure Configuration Management

[22] Standards Mapping - OWASP Top 10 2007 A9 Insecure Communications

[23] Standards Mapping - OWASP Top 10 2010 A9 Insufficient Transport Layer Protection

[24] Standards Mapping - OWASP Top 10 2021 A07 Identification and Authentication Failures

[25] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 Requirement 4.1, Requirement 6.5.10

[26] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 Requirement 4.1, Requirement 6.3.1.4, Requirement 6.5.9

[27] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 Requirement 4.1, Requirement 6.5.4

[28] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 4.1, Requirement 6.5.4

[29] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 4.1, Requirement 6.5.4

[30] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 4.1, Requirement 6.5.4

[31] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 4.1, Requirement 6.5.4

[32] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0 Requirement 4.2.1, Requirement 6.2.4

[33] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0.1 Requirement 4.2.1, Requirement 6.2.4

[34] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 5.3 - Authentication and Access Control

[35] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 5.3 - Authentication and Access Control

[36] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 5.3 - Authentication and Access Control, Control Objective C.2.1.2 - Web Software Access Controls

[37] Standards Mapping - SANS Top 25 2010 Porous Defenses - CWE ID 311

[38] Standards Mapping - SANS Top 25 2011 Porous Defenses - CWE ID 311

[39] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3250.1 CAT I, APP3250.2 CAT I, APP3250.3 CAT II, APP3250.4 CAT II

[40] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3250.1 CAT I, APP3250.2 CAT I, APP3250.3 CAT II, APP3250.4 CAT II

[41] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3250.1 CAT I, APP3250.2 CAT I, APP3250.3 CAT II, APP3250.4 CAT II

[42] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3250.1 CAT I, APP3250.2 CAT I, APP3250.3 CAT II, APP3250.4 CAT II

[43] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3250.1 CAT I, APP3250.2 CAT I, APP3250.3 CAT II, APP3250.4 CAT II

[44] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3250.1 CAT I, APP3250.2 CAT I, APP3250.3 CAT II, APP3250.4 CAT II

[45] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3250.1 CAT I, APP3250.2 CAT I, APP3250.3 CAT II, APP3250.4 CAT II

[46] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-001650 CAT II

[47] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-001650 CAT II

[48] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-001650 CAT II

[49] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-001650 CAT II

[50] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-001650 CAT II

[51] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-001650 CAT II

[52] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-001650 CAT II

[53] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-001650 CAT II

[54] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-001650 CAT II

[55] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-001650 CAT II

[56] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-001650 CAT II

[57] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-001650 CAT II

[58] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-001650 CAT II

[59] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-001650 CAT II

[60] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-001650 CAT II

[61] Standards Mapping - Web Application Security Consortium Version 2.00 Insufficient Authentication (WASC-01)

[62] Standards Mapping - Web Application Security Consortium 24 + 2 Insufficient Authentication

desc.dataflow.objc.biometric_authentication_insecure_touch_id_implementation

Abstract

The application uses the LocalAuthentication framework to authenticate the user which may not be sufficient for apps requiring heightened security controls.

Explanation


    ...
    let context:LAContext = LAContext();  
    var error:NSError?  
    let reason:String = "Please authenticate using the Touch ID sensor."
    
    if (context.canEvaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, error: &error))  {
        context.evaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, localizedReason: reason, reply: { (success, error) -> Void in
            if (success) {
                // Fingerprint was authenticated
            }
            else {
                // Fingerprint could not be authenticated
            }
        })
    }
    ...