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CVE-2018-21058: Google Android: Use of a Broken or Risky Cryptographic Algorithm

CVE-2018-21058 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 N(7.0), O(8.0) (exynos7420 or Exynos 8890/8996 chipsets) software. Cache attacks can occur against the Keymaster AES-GCM implementation because T-Tables are used; the Cryptography Extension (CE) is not used. The Samsung ID is SVE-2018-12761 (September 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-327: Use of a Broken or Risky Cryptographic Algorithm

The product uses a broken or risky cryptographic algorithm or protocol.

Affected products

  • Google Android: 7.0; 8.0

References