CVE-2021-26403

MEDIUMNVD 6.56.5—

6.5

Insufficient checks in SEV may lead to a malicious hypervisor disclosing the launch secret potentially resulting in compromise of VM confidentiality.

CVSS v3: 6.5
EG Score: 6.5(medium)
EPSS: 9.1%
KEV: Not listed

Published

January 11, 2023

Last Modified

April 8, 2025

References (2)

psirt@amdhttps://www.amd.com/en/corporate/product-security/bulletin/AMD-SB-1032
af854a3a-2127-422b-91ae-364da2661108https://www.amd.com/en/corporate/product-security/bulletin/AMD-SB-1032

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-345Insufficient Verification of Data Authenticity

Data Freshness Timeline

(refreshed 11× in last 7d / 18× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-02 20:11 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-06-01 13:50 UTCepss_batch
2026-06-01 13:50 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 00:15 UTCepss_batch
2026-05-29 13:42 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-27 13:39 UTCepss_batch
2026-05-27 13:39 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-25 08:53 UTCEG score recompute
2026-05-25 08:53 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2021-26403?

CVE-2021-26403 is a medium vulnerability published on January 11, 2023. Insufficient checks in SEV may lead to a malicious hypervisor disclosing the launch secret potentially resulting in compromise of VM confidentiality.

When was CVE-2021-26403 disclosed?

CVE-2021-26403 was first published in the National Vulnerability Database on January 11, 2023, with the most recent update on April 8, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-26403 actively exploited?

CVE-2021-26403 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 9.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-26403?

CVE-2021-26403 has a CVSS v3 base score of 6.5 (NVD).

How do I remediate CVE-2021-26403?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-26403, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-26403

Explore →

Is Your Infrastructure Affected by CVE-2021-26403?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs

CVE-2021-26403

📅 Published

🔄 Last Modified

🔗 References (2)

Weakness Classification(1)

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-26403?

🔗 Related CVEs(same CWE)

Same CWE

Published

Last Modified

References (2)

Frequently asked(5)

Related CVEs(same CWE)