Kingdom: Code Quality

Poor code quality leads to unpredictable behavior. From a user's perspective that often manifests itself as poor usability. For an attacker it provides an opportunity to stress the system in unexpected ways.

Intent Manipulation: Mutable Pending Intent

Abstract
A PendingIntent has been detected that has its flag value set to FLAG_MUTABLE. Pending intents created with the flag value of FLAG_MUTABLE are susceptible to having unspecified Intent fields set downstream, which can modify the capacity of the Intent and leave the system open to vulnerability.
Explanation
Allowing modification of the underlying Intent of a PendingIntent after its creation can leave a system open to attack. This mostly depends on the overall capability of the underlying Intent. In most cases, it is best practice to prevent potential issues by setting the PendingIntent flag to FLAG_IMMUTABLE.

Example 1: The following includes a PendingIntent created with a flag value of FLAG_MUTABLE.


...
val intent_flag_mut = Intent(Intent.ACTION_GTALK_SERVICE_DISCONNECTED, Uri.EMPTY, this, DownloadService::class.java)
val flag_mut = PendingIntent.FLAG_MUTABLE

val pi_flagmutable = PendingIntent.getService(
    this,
    0,
    intent_flag_mut,
    flag_mut
)
...
References
[1] Remediation for Implicit PendingIntent Vulnerability
[2] Standards Mapping - Common Weakness Enumeration CWE ID 99
[3] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-001094
[4] Standards Mapping - General Data Protection Regulation (GDPR) Indirect Access to Sensitive Data
[5] Standards Mapping - NIST Special Publication 800-53 Revision 4 SC-5 Denial of Service Protection (P1)
[6] Standards Mapping - NIST Special Publication 800-53 Revision 5 SC-5 Denial of Service Protection
[7] Standards Mapping - OWASP Top 10 2004 A9 Application Denial of Service
[8] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 Requirement 6.5.1
[9] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 Requirement 6.3.1.1, Requirement 6.5.4
[10] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 Requirement 6.5.8
[11] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 6.5.8
[12] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.8
[13] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.8
[14] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.8
[15] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0 Requirement 6.2.4
[16] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0.1 Requirement 6.2.4
[17] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP6080 CAT II
[18] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP6080 CAT II
[19] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP6080 CAT II
[20] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP6080 CAT II
[21] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP6080 CAT II
[22] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP6080 CAT II
[23] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP6080 CAT II
[24] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002400 CAT II
[25] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002400 CAT II
[26] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002400 CAT II
[27] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002400 CAT II
[28] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002400 CAT II
[29] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002400 CAT II
[30] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002400 CAT II
[31] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002400 CAT II
[32] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002400 CAT II
[33] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002400 CAT II
[34] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002400 CAT II
[35] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002400 CAT II
[36] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002400 CAT II
[37] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002400 CAT II
[38] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002400 CAT II
[39] Standards Mapping - Web Application Security Consortium Version 2.00 Denial of Service (WASC-10)
[40] Standards Mapping - Web Application Security Consortium 24 + 2 Denial of Service
desc.controlflow.java.intent_manipulation_mutable_pending_intent