High severity · published Feb 24, 2021
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
8.8
CVSS
45.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)45.1% · higher than 99% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ES
ESXi · VMware
6.5; 6.5; 6.5; 6.5; 6.5; 6.5; +34 more · source: NVD
CF
Cloud Foundation · Vmware
3.0 before 3.10.1.2; 4.0 before 4.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21974
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21974
Exploit
http://packetstormsecurity.com/files/162957/VMware-ESXi-OpenSLP-Heap-Overflow.html
Vendor Advisory
https://www.vmware.com/security/advisories/VMSA-2021-0002.html
Third Party Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-250/
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