CVE-2021-21974

Public Exploit

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.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 59.90% Top 5%
Vendor Advisory vmware.com
Affected: n/a VMware ESXi
Affected: n/a VMware Cloud Foundation
Published at:
Updated at:

References

Link Tags
https://www.vmware.com/security/advisories/VMSA-2021-0002.html vendor advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-250/ vdb entry third party advisory
http://packetstormsecurity.com/files/162957/VMware-ESXi-OpenSLP-Heap-Overflow.html exploit vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-21974?
CVE-2021-21974 has been scored as a high severity vulnerability.
How to fix CVE-2021-21974?
To fix CVE-2021-21974, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21974 being actively exploited in the wild?
It is possible that CVE-2021-21974 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~60% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21974?
CVE-2021-21974 affects n/a VMware ESXi, n/a VMware Cloud Foundation.
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