CVE-2020-0204:Time-of-Check/Time-of-Use vulnerability in Android's InstallPackage function allows local privilege escalation by bypassing signature verification during OS updates.

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Description Preview

CVE-2020-0204 is a Time-of-Check/Time-of-Use (TOCTOU) vulnerability discovered in Android's package installation system. The flaw exists specifically in the InstallPackage function of package.cpp, where there is a race condition between the time when a package's signature is verified and when the package is actually installed. This vulnerability could allow an attacker to bypass signature verification checks during OS updates, potentially enabling the installation of malicious packages with elevated privileges. The vulnerability affects Android 10 and requires user interaction to be exploited.

Overview

This vulnerability (CWE-367: Time-of-Check Time-of-Use Race Condition) allows a local attacker to bypass Android's signature verification mechanism during package installation. The issue occurs in the InstallPackage function where there's a race condition between the verification of a ZIP file's signature and its actual use. An attacker could exploit this vulnerability to install unauthorized OS updates, potentially gaining elevated privileges on the device. The attack requires user interaction and local access to the device. This vulnerability is particularly concerning as it could allow for persistent compromise of Android devices through malicious system updates.

Remediation

To address this vulnerability, users should:

  1. Update to the latest Android security patch level, specifically the June 2020 security update or later.
  2. Only install system updates from official sources through the device's built-in update mechanism.
  3. Be cautious about granting installation permissions to applications, especially from unknown sources.
  4. System administrators should ensure all managed Android devices are kept up-to-date with the latest security patches.
  5. Developers should implement proper file access controls and avoid race conditions by using atomic operations where possible.

References

  1. Android Security Bulletin (Pixel): https://source.android.com/security/bulletin/pixel/2020-06-01
  2. CWE-367: Time-of-Check Time-of-Use Race Condition: https://cwe.mitre.org/data/definitions/367.html
  3. Android Security ID: A-136498130

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. Finance and Insurance
    Finance and Insurance
  2. Manufacturing
    Manufacturing
  3. Accommodation & Food Services
    Accommodation & Food Services
  4. Administrative, Support, Waste Management & Remediation Services
    Administrative, Support, Waste Management & Remediation Services
  5. Agriculture, Forestry Fishing & Hunting
    Agriculture, Forestry Fishing & Hunting
  6. Arts, Entertainment & Recreation
    Arts, Entertainment & Recreation
  7. Construction
    Construction
  8. Educational Services
    Educational Services
  9. Health Care & Social Assistance
    Health Care & Social Assistance
  10. Information
    Information
  11. Management of Companies & Enterprises
    Management of Companies & Enterprises
  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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