CVE-2021-21556: Buffer Overflow

Published Jun 14, 2021
·
Updated

Dell PowerEdge R640, R740, R740XD, R840, R940, R940xa, MX740c, MX840c, and T640 Server BIOS contain a stack-based buffer overflow vulnerability in systems with NVDIMM-N 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.

Affected Software

18 affected components
Dell Poweredge R640 Firmware<2.11.2
Dell PowerEdge R640
Dell Poweredge R740 Firmware<2.11.2
Dell Poweredge R740
Dell Poweredge R740xd Firmware<2.11.2
Dell Poweredge R740xd
Dell Poweredge R940 Firmware<2.11.2
Dell Poweredge R940
Dell Poweredge R840 Firmware<2.11.2
Dell Poweredge R840
Dell Poweredge R940xa Firmware<2.11.2
Dell Poweredge R940xa
Dell Poweredge T640 Firmware<2.11.2
Dell Poweredge T640
Dell Poweredge Mx740c Firmware<2.11.2
Dell Poweredge Mx740c
Dell Poweredge Mx840c Firmware<2.11.2
Dell Poweredge Mx840c

Event History

Jun 14, 2021
CVE Published
via MITRE·07:10 PM
Data Sourced
via MITRE·07:10 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the vulnerability ID for this Dell PowerEdge Server BIOS vulnerability?

The vulnerability ID for this Dell PowerEdge Server BIOS vulnerability is CVE-2021-21556.

2

What is the severity rating of CVE-2021-21556?

The severity rating of CVE-2021-21556 is high.

3

Which Dell PowerEdge server models are affected by this vulnerability?

The Dell PowerEdge R640, R740, R740XD, R840, R940, R940xa, MX740c, MX840c, and T640 server models are affected by this vulnerability.

4

What is the impact of exploiting CVE-2021-21556?

Exploiting CVE-2021-21556 can lead to a denial of service (DoS) condition.

5

Where can I find more information about this vulnerability?

You can find more information about this vulnerability at the following reference link: [Dell Support KB Article](https://www.dell.com/support/kbdoc/000187958)

Contact

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