CVE-2021-26408

Insufficient validation of elliptic curve points in SEV-legacy firmware may compromise SEV-legacy guest migration potentially resulting in loss of guest's integrity or confidentiality.

Published: 2022-05-10 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-26408 is rated Low Risk (34.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.26%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2021-26408

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 0.06% 0.26% +0.20%
2 2025-03-17 0.04% 0.06% +0.01%
3 2023-03-07 — 0.04% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-26408

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.1 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N 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:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 1.8 5.2 [email protected]
6.6 2.0 MEDIUM
AV:L/AC:L/Au:N/C:C/I:C/A:N Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:N)
No availability impact.
 3.9 9.2 [email protected]

Weakness enumeration for CVE-2021-26408

Affected software / configurations for CVE-2021-26408

Vendor Product Version Raw CPE
amd epyc_7002_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7002_firmware:*:*:*:*:*:*:*:*
amd epyc_7001_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7001_firmware:*:*:*:*:*:*:*:*
amd epyc_7232p_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7232p_firmware:*:*:*:*:*:*:*:*
amd epyc_7252_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7252_firmware:*:*:*:*:*:*:*:*
amd epyc_7262_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7262_firmware:*:*:*:*:*:*:*:*
amd epyc_7272_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7272_firmware:*:*:*:*:*:*:*:*
amd epyc_7282_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7282_firmware:*:*:*:*:*:*:*:*
amd epyc_7302_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7302_firmware:*:*:*:*:*:*:*:*
amd epyc_7302p_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7302p_firmware:*:*:*:*:*:*:*:*
amd epyc_7352_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7352_firmware:*:*:*:*:*:*:*:*
amd epyc_7402_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7402_firmware:*:*:*:*:*:*:*:*
amd epyc_7402p_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7402p_firmware:*:*:*:*:*:*:*:*
amd epyc_7452_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7452_firmware:*:*:*:*:*:*:*:*
amd epyc_7502_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7502_firmware:*:*:*:*:*:*:*:*
amd epyc_7502p_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7502p_firmware:*:*:*:*:*:*:*:*
amd epyc_7532_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7532_firmware:*:*:*:*:*:*:*:*
amd epyc_7542_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7542_firmware:*:*:*:*:*:*:*:*
amd epyc_7552_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7552_firmware:*:*:*:*:*:*:*:*
amd epyc_7642_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7642_firmware:*:*:*:*:*:*:*:*
amd epyc_7662_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7662_firmware:*:*:*:*:*:*:*:*
amd epyc_7702_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7702_firmware:*:*:*:*:*:*:*:*
amd epyc_7702p_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7702p_firmware:*:*:*:*:*:*:*:*
amd epyc_7742_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7742_firmware:*:*:*:*:*:*:*:*
amd epyc_7f32_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7f32_firmware:*:*:*:*:*:*:*:*
amd epyc_7f52_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7f52_firmware:*:*:*:*:*:*:*:*
amd epyc_7f72_firmware < romepi-sp3_1.0.0.c cpe:2.3:o:amd:epyc_7f72_firmware:*:*:*:*:*:*:*:*
amd epyc_7251_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7251_firmware:*:*:*:*:*:*:*:*
amd epyc_7281_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7281_firmware:*:*:*:*:*:*:*:*
amd epyc_7301_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7301_firmware:*:*:*:*:*:*:*:*
amd epyc_7351_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7351_firmware:*:*:*:*:*:*:*:*
amd epyc_7351p_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7351p_firmware:*:*:*:*:*:*:*:*
amd epyc_7401_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7401_firmware:*:*:*:*:*:*:*:*
amd epyc_7401p_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7401p_firmware:*:*:*:*:*:*:*:*
amd epyc_7451_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7451_firmware:*:*:*:*:*:*:*:*
amd epyc_7501_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7501_firmware:*:*:*:*:*:*:*:*
amd epyc_7551_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7551_firmware:*:*:*:*:*:*:*:*
amd epyc_7551p_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7551p_firmware:*:*:*:*:*:*:*:*
amd epyc_7601_firmware < naplespi-sp3_1.0.0.g cpe:2.3:o:amd:epyc_7601_firmware:*:*:*:*:*:*:*:*

References for CVE-2021-26408

cvelogic Threat Intelligence