How severe is CVE-2021-26348?

CVE-2021-26348 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 none, integrity high, and availability none.

Is CVE-2021-26348 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26348?

CVE-2021-26348 primarily affects Amd Epyc 7763 Firmware. In total, 23 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-26348?

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

When was CVE-2021-26348 published?

CVE-2021-26348 was published on 2022-05-11 and last updated on 2026-06-17.

CVE-2021-26348

CVE-2021-26348 is a medium-severity vulnerability in Amd Epyc 7763 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)
CVSS v2: 2.1
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Amd Epyc 7763 Firmware
Published: 2022-05-11
Last modified: 2026-06-17

Description

Failure to flush the Translation Lookaside Buffer (TLB) of the I/O memory management unit (IOMMU) may lead an IO device to write to memory it should not be able to access, resulting in a potential loss of integrity.

Frequently asked questions

What is CVE-2021-26348?: Failure to flush the Translation Lookaside Buffer (TLB) of the I/O memory management unit (IOMMU) may lead an IO device to write to memory it should not be able to access, resulting in a potential loss of integrity.
How severe is CVE-2021-26348?: CVE-2021-26348 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 none, integrity high, and availability none.
Is CVE-2021-26348 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26348?: CVE-2021-26348 primarily affects Amd Epyc 7763 Firmware. In total, 23 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-26348?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-26348 published?: CVE-2021-26348 was published on 2022-05-11 and last updated on 2026-06-17.

References

https://www.amd.com/en/corporate/product-security/bulletin/amd-sb-1028

Affected products (23)

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_7543p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7543_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7513_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7453_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_74f3_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_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_7773x_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7473x_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7573x_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:amd:epyc_7373x_firmware:*:*:*:*:*:*:*:*

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