CVE-2021-21556
Status: ModifiedMedium (6.7)—
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.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
- Base score: 6.7
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.31%
- Percentile among all scored CVEs: 21
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (9)
CWEs
- CWE-121
- CWE-787
References
Raw JSON (NVD)
Show
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