CVE-2021-21974
CVSS v3
8.8
HIGH
EPSS Score
45.1 %
exploit probability
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
OpenSLP as used in ESXi (7.0 before ESXi70U1c-17325551, 6.7 before ESXi670-202102401-SG, 6.5 before ESXi650-202102101-SG) has a heap-overflow vulnerability. A malicious actor residing within the same network segment as ESXi who has access to port 427 may be able to trigger the heap-overflow issue in OpenSLP service resulting in remote code execution.
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Published
- 2021-02-24
- Last Modified
- 2026-06-02
Frequently asked questions
What is CVE-2021-21974?
OpenSLP as used in ESXi (7.0 before ESXi70U1c-17325551, 6.7 before ESXi670-202102401-SG, 6.5 before ESXi650-202102101-SG) has a heap-overflow vulnerability. A malicious actor residing within the same network segment as ESXi who has access to port 427 may be able to trigger the heap-overflow issue in OpenSLP service resulting in remote code execution.
Is CVE-2021-21974 actively exploited?
Active exploitation of CVE-2021-21974 has not been confirmed. The EPSS score is 45.1%, indicating the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-21974?
CVE-2021-21974 has a CVSS v3 base score of 8.8 (HIGH severity), with vector string CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
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