CVE-2021-26396

Insufficient validation of address mapping to IO in ASP (AMD Secure Processor) may result in a loss of memory integrity in the SNP guest.

Published: 2023-01-11 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-26396 is rated Low Risk (18.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.11%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

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-2021-26396

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 0.03% 0.11% +0.09%
2 2026-03-13 0.07% 0.03% -0.04%
3 2026-01-15 — 0.07% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-26396

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.4 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
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:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.8 2.5 [email protected]
4.4 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
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:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.8 2.5 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2021-26396

Affected software / configurations for CVE-2021-26396

Vendor Product Version Raw CPE
amd epyc_7003_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7003_firmware:*:*:*:*:*:*:*:*
amd epyc_72f3_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_72f3_firmware:*:*:*:*:*:*:*:*
amd epyc_7313_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7313_firmware:*:*:*:*:*:*:*:*
amd epyc_7313p_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7313p_firmware:*:*:*:*:*:*:*:*
amd epyc_7343_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7343_firmware:*:*:*:*:*:*:*:*
amd epyc_7373x_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7373x_firmware:*:*:*:*:*:*:*:*
amd epyc_73f3_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_73f3_firmware:*:*:*:*:*:*:*:*
amd epyc_7413_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7413_firmware:*:*:*:*:*:*:*:*
amd epyc_7443_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7443_firmware:*:*:*:*:*:*:*:*
amd epyc_7443p_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7443p_firmware:*:*:*:*:*:*:*:*
amd epyc_7453_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7453_firmware:*:*:*:*:*:*:*:*
amd epyc_74f3_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_74f3_firmware:*:*:*:*:*:*:*:*
amd epyc_7513_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7513_firmware:*:*:*:*:*:*:*:*
amd epyc_7543_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7543_firmware:*:*:*:*:*:*:*:*
amd epyc_7543p_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7543p_firmware:*:*:*:*:*:*:*:*
amd epyc_7573x_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7573x_firmware:*:*:*:*:*:*:*:*
amd epyc_75f3_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_75f3_firmware:*:*:*:*:*:*:*:*
amd epyc_7643_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7643_firmware:*:*:*:*:*:*:*:*
amd epyc_7663_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7663_firmware:*:*:*:*:*:*:*:*
amd epyc_7713_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7713_firmware:*:*:*:*:*:*:*:*
amd epyc_7713p_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7713p_firmware:*:*:*:*:*:*:*:*
amd epyc_7743_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7743_firmware:*:*:*:*:*:*:*:*
amd epyc_7763_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7763_firmware:*:*:*:*:*:*:*:*
amd epyc_7773x_firmware < milanpi-sp3_1.0.0.9 cpe:2.3:o:amd:epyc_7773x_firmware:*:*:*:*:*:*:*:*

References for CVE-2021-26396

cvelogic Threat Intelligence