How severe is CVE-2021-26401?

CVE-2021-26401 has a CVSS 3.x base score of 5.6, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-26401 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26401?

CVE-2021-26401 primarily affects Amd Athlon X4 940 Firmware. In total, 126 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-26401?

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

When was CVE-2021-26401 published?

CVE-2021-26401 was published on 2022-03-11 and last updated on 2026-06-17.

CVE-2021-26401

CVE-2021-26401 is a medium-severity vulnerability in Amd Athlon X4 940 Firmware with a CVSS 3.x base score of 5.6. 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 5.6)
CVSS v2: 1.9
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Amd Athlon X4 940 Firmware
Published: 2022-03-11
Last modified: 2026-06-17

Description

LFENCE/JMP (mitigation V2-2) may not sufficiently mitigate CVE-2017-5715 on some AMD CPUs.

Frequently asked questions

What is CVE-2021-26401?: LFENCE/JMP (mitigation V2-2) may not sufficiently mitigate CVE-2017-5715 on some AMD CPUs.
How severe is CVE-2021-26401?: CVE-2021-26401 has a CVSS 3.x base score of 5.6, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-26401 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26401?: CVE-2021-26401 primarily affects Amd Athlon X4 940 Firmware. In total, 126 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-26401?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-26401 published?: CVE-2021-26401 was published on 2022-03-11 and last updated on 2026-06-17.

References

Affected products (126)

cpe:2.3:o:amd:athlon_x4_940_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_950_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_970_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_835_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_845_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_830_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_840_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_860k_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_870k_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_880k_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_750_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:athlon_x4_760k_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_pro_5995wx_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_pro_5975wx_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_pro_5965wx_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_pro_5955wx_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_pro_5945wx_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_2990wx_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_2970wx_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_2950x_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_2920x_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_threadripper_3970x_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a12-9730p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a12-9700p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a10-9630p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a10-9600p_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a9-9420_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a9-9410_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a6-9220_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a6-9220c_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a6-9210_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:a4-9120_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_7_2700x_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_7_2700_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_5_2600x_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_5_2600_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_9_3950x_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_9_3900x_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_7_3800x_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:amd:ryzen_7_3700x_firmware:-:*:*:*:*:*:*:*

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