How severe is CVE-2021-21554?

CVE-2021-21554 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2021-21554 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21554?

CVE-2021-21554 primarily affects Dell Poweredge R640 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-21554?

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

When was CVE-2021-21554 published?

CVE-2021-21554 was published on 2021-06-14 and last updated on 2026-06-17.

CVE-2021-21554

CVE-2021-21554 is a medium-severity vulnerability in Dell Poweredge R640 Firmware with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 7.2
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Dell Poweredge R640 Firmware
Published: 2021-06-14
Last modified: 2026-06-17

Description

Dell PowerEdge R640, R740, R740XD, R840, R940, R940xa, MX740c, MX840c, and, Dell Precision 7920 Rack Workstation BIOS contain a stack-based buffer overflow vulnerability in systems with Intel Optane DC Persistent Memory installed. A local malicious user with high privileges may potentially exploit this vulnerability, leading to a denial of Service, arbitrary code execution, or information disclosure in UEFI or BIOS Preboot Environment.

Frequently asked questions

What is CVE-2021-21554?: Dell PowerEdge R640, R740, R740XD, R840, R940, R940xa, MX740c, MX840c, and, Dell Precision 7920 Rack Workstation BIOS contain a stack-based buffer overflow vulnerability in systems with Intel Optane DC Persistent Memory installed. A local malicious user with high privileges may potentially exploit this vulnerability, leading to a denial of Service, arbitrary code execution, or information disclosure in UEFI or BIOS Preboot Environment.
How severe is CVE-2021-21554?: CVE-2021-21554 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2021-21554 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21554?: CVE-2021-21554 primarily affects Dell Poweredge R640 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-21554?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-21554 published?: CVE-2021-21554 was published on 2021-06-14 and last updated on 2026-06-17.

References

https://www.dell.com/support/kbdoc/000187958

Affected products (9)

cpe:2.3:o:dell:poweredge_r640_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:dell:poweredge_r740_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:dell:poweredge_r740xd_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:dell:poweredge_r940_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:dell:poweredge_r840_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:dell:poweredge_r940xa_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:dell:poweredge_mx740c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:dell:poweredge_mx840c_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:dell:precision_7920_firmware:-:*:*:*:*:*:*:*

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