How severe is CVE-2021-26371?

CVE-2021-26371 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-26371 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26371?

CVE-2021-26371 primarily affects Amd Epyc 7773x Firmware. In total, 128 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-26371?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-26371 published?

CVE-2021-26371 was published on 2023-05-09 and last updated on 2026-06-17.

CVE-2021-26371

CVE-2021-26371 is a medium-severity vulnerability in Amd Epyc 7773x Firmware with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Amd Epyc 7773x Firmware
Published: 2023-05-09
Last modified: 2026-06-17

Description

A compromised or malicious ABL or UApp could send a SHA256 system call to the bootloader, which may result in exposure of ASP memory to userspace, potentially leading to information disclosure.

Frequently asked questions

What is CVE-2021-26371?: A compromised or malicious ABL or UApp could send a SHA256 system call to the bootloader, which may result in exposure of ASP memory to userspace, potentially leading to information disclosure.
How severe is CVE-2021-26371?: CVE-2021-26371 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-26371 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26371?: CVE-2021-26371 primarily affects Amd Epyc 7773x Firmware. In total, 128 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-26371?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-26371 published?: CVE-2021-26371 was published on 2023-05-09 and last updated on 2026-06-17.

References

Affected products (128)

cpe:2.3:o:amd:epyc_7773x_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7763_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7713p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7713_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7663_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7643_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_75f3_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7573x_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7543p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7543_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7513_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_74f3_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7473x_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7453_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7443p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7443_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7413_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_73f3_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7373x_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7343_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7313p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7313_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_72f3_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7003_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7002_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7232p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7252_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7262_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7272_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7282_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7302_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7302p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7352_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7402_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7402p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7452_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7502_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7502p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7532_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7542_firmware:*:*:*:*:*:*:*:*

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