CVE-2021-0372:Permission bypass vulnerability in Android's RemoteMediaSlice.java allows local privilege escalation.

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Description Preview

CVE-2021-0372 is a vulnerability in Android 11's RemoteMediaSlice.java file, specifically in the getMediaOutputSliceAction function. The issue involves an unsafe PendingIntent implementation that could allow a malicious application to bypass permissions. This vulnerability could lead to local escalation of privilege when executed with User execution privileges. The exploitation of this vulnerability does not require any user interaction, making it particularly concerning for Android security.

Overview

This vulnerability (CVE-2021-0372) is classified as CWE-732, which relates to incorrect permission assignment for critical resources. The issue exists in Android 11's media output handling functionality, specifically in the RemoteMediaSlice.java component. The vulnerable function getMediaOutputSliceAction creates a PendingIntent without properly restricting its scope, allowing potential attackers to hijack the intent and execute operations with elevated privileges. Since no user interaction is required for exploitation, a malicious application could silently exploit this vulnerability to gain additional permissions beyond what it was granted during installation.

Remediation

Users should update their Android devices to the latest security patch level that addresses this vulnerability. Google released a fix for this issue in the March 2021 security bulletin for Pixel devices. Device manufacturers may have incorporated this fix in subsequent security updates.

For developers:

  1. When creating PendingIntent objects, always specify the exact component to be called and use explicit intents.
  2. Set appropriate flags like FLAG_IMMUTABLE or FLAG_NO_CREATE to prevent intent hijacking.
  3. Avoid using implicit intents with PendingIntent whenever possible.
  4. Review your application's permission handling, especially when dealing with system services.

References

  1. Android Security Bulletin (Pixel) - March 2021: https://source.android.com/security/bulletin/pixel/2021-03-01
  2. CWE-732: Incorrect Permission Assignment for Critical Resource: https://cwe.mitre.org/data/definitions/732.html
  3. Android ID: A-174047735

Industry ExposureMost to least
This section illustrates the prevalence of a specific Common Vulnerabilities and Exposures (CVE) across various industries based on customer reports. The ranking displays industries from the most to least affected by this particular vulnerability, offering valuable insight into where this CVE has been most frequently observed. This information can help organizations within these sectors prioritize their security efforts, understand their relative risk exposure compared to their peers, and focus remediation strategies where they are most needed. By understanding the industry-specific impact, organizations can make more informed decisions regarding patching, resource allocation, and overall risk management related to this CVE.

  1. Accommodation & Food Services
    Accommodation & Food Services
  2. Administrative, Support, Waste Management & Remediation Services
    Administrative, Support, Waste Management & Remediation Services
  3. Agriculture, Forestry Fishing & Hunting
    Agriculture, Forestry Fishing & Hunting
  4. Arts, Entertainment & Recreation
    Arts, Entertainment & Recreation
  5. Construction
    Construction
  6. Educational Services
    Educational Services
  7. Finance and Insurance
    Finance and Insurance
  8. Health Care & Social Assistance
    Health Care & Social Assistance
  9. Information
    Information
  10. Management of Companies & Enterprises
    Management of Companies & Enterprises
  11. Manufacturing
    Manufacturing
  12. Mining
    Mining
  13. Other Services (except Public Administration)
    Other Services (except Public Administration)
  14. Professional, Scientific, & Technical Services
    Professional, Scientific, & Technical Services
  15. Public Administration
    Public Administration
  16. Real Estate Rental & Leasing
    Real Estate Rental & Leasing
  17. Retail Trade
    Retail Trade
  18. Transportation & Warehousing
    Transportation & Warehousing
  19. Utilities
    Utilities
  20. Wholesale Trade
    Wholesale Trade

Focus on What Matters

  1. See Everything.
  2. Identify True Risk.
  3. Proactively Mitigate Threats.

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