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CVE-2018-21065: Google Android: Integer Underflow (Wrap or Wraparound)

CVE-2018-21065 is rated critical with a CVSS v3.1 base score of 9.8 and NVD lists Google Android as the affected product. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

An issue was discovered on Samsung mobile devices with M(6.0), N(7.x), and O(8.x) software. There is an integer underflow in eCryptFS because of a missing size check. The Samsung ID is SVE-2017-11855 (August 2018).

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-191: Integer Underflow (Wrap or Wraparound)

The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.

Affected products

  • Google Android: 6.0; 7.0; 7.1.0; 7.1.1; 7.1.2; 8.0; 8.1

References