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CVE-2018-8933: Amd Epyc Server Firmware: Incorrect Permission Assignment for Critical Resource

CVE-2018-8933 is rated critical with a CVSS v3.0 base score of 9.0 and NVD lists Amd Epyc Server Firmware 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

The AMD EPYC Server processor chips have insufficient access control for protected memory regions, aka FALLOUT-1, FALLOUT-2, and FALLOUT-3.

Severity breakdown

CVSS v3.0 9.0: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
Attack complexity: High. Success depends on conditions outside the attacker’s control.
Privileges required: None. No account or prior access is needed.
User interaction: None. No action from any user is needed.
Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
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-732: Incorrect Permission Assignment for Critical Resource

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.

Affected products

Amd Epyc Server Firmware: all versions listed by NVD