CVE-2021-46756

Insufficient validation of inputs in SVC_MAP_USER_STACK in the ASP (AMD Secure Processor)...

9.1 Critical

Insufficient validation of inputs in SVC_MAP_USER_STACK in the ASP (AMD Secure Processor) bootloader may allow an attacker with a malicious Uapp or ABL to send malformed or invalid syscall to the bootloader resulting in a potential denial of service and loss of integrity.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: High
Availability: High

Exploit likelihood

0.65%Up 0.6 points since May 10, 2023

What each source reports

NVD Score used 9.1

Record: CVE-2021-46756
CVSS 3.1: 9.1 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Weakness: CWE-20
Updated: 2026-11-02

CVE List 9.1

Record: CVE-2021-46756
CVSS 3.1: 9.1 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Updated: 2026-11-02

EUVDEUVD-2021-33412 9.1

Record: EUVD-2021-33412
CVSS 3.1: 9.1 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Updated: 2026-11-03

GitHub AdvisoriesGHSA-p57x-q6x3-v235 9.1

Insufficient validation of inputs in SVC_MAP_USER_STACK in the ASP (AMD Secure Processor)...

Record: GHSA-p57x-q6x3-v235
CVSS 3.1: 9.1 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Weakness: CWE-20
Updated: 2026-11-02

Affected products

Show 69 moreShow less

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases, published	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2021-46756 is a critical vulnerability (CVSS 9.1) in Amd 1st Gen Amd Epyc™ Processors, published May 9, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.65%, the 51st percentile. No source names a fixed version.