CVE-2021-46755

Failure to unmap certain SysHub mappings in error paths of the ASP (AMD Secure Processor) bootloader may allow an attacker with a malicious bootloader to exhaust the SysHub resources resulting in a potential denial of service.

Published: 2023-05-09 Last update: 2025-01-28 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-46755 is rated Moderate Risk (45.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.62%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-46755

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.54% 0.62% +0.08%
2 2026-05-31 0.43% 0.54% +0.11%
3 2026-05-24 — 0.43% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-46755

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2021-46755

Affected software / configurations for CVE-2021-46755

Vendor Product Version Raw CPE
amd ryzen_5500_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5500_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5500_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5500_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5600_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5600_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5600_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5600_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5600g_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5600g_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5600g_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5600g_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5600x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5600x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5600x_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5600x_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5700g_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5700g_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5700g_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5700g_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5700x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5700x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5700x_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5700x_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5800x3d_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5800x3d_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5800x3d_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5800x3d_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5800x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5800x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5800x_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5800x_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5900x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5900x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5900x_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5900x_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_5950x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_5950x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_5950x_firmware comboam4v2_pi_1.2.0.6 cpe:2.3:o:amd:ryzen_5950x_firmware:comboam4v2_pi_1.2.0.6:*:*:*:*:*:*:*
amd ryzen_3100_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3100_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3100_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3100_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3300x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3300x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3300x_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3300x_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3500_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3500_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3500_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3500_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3500x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3500x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3500x_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3500x_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3600_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3600_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3600_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3600_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3600x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3600x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3600x_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3600x_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3600xt_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3600xt_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3600xt_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3600xt_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3800x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3800x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3800x_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3800x_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3800xt_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3800xt_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3800xt_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3800xt_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3900_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3900_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3900_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3900_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3900x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3900x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3900x_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3900x_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3900xt_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3900xt_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3900xt_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3900xt_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*
amd ryzen_3950x_firmware comboam4_v2_pi_1.2.0.8 cpe:2.3:o:amd:ryzen_3950x_firmware:comboam4_v2_pi_1.2.0.8:*:*:*:*:*:*:*
amd ryzen_3950x_firmware comboam4pi_1.0.0.9 cpe:2.3:o:amd:ryzen_3950x_firmware:comboam4pi_1.0.0.9:*:*:*:*:*:*:*

References for CVE-2021-46755

cvelogic Threat Intelligence