How severe is CVE-2021-21995?

CVE-2021-21995 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-21995 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21995?

CVE-2021-21995 primarily affects Vmware Cloud Foundation. In total, 238 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-21995?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-21995 published?

CVE-2021-21995 was published on 2021-07-13 and last updated on 2026-06-17.

CVE-2021-21995

CVE-2021-21995 is a high-severity vulnerability in Vmware Cloud Foundation with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Vmware Cloud Foundation
Published: 2021-07-13
Last modified: 2026-06-17

Description

OpenSLP as used in ESXi has a denial-of-service vulnerability due a heap out-of-bounds read issue. A malicious actor with network access to port 427 on ESXi may be able to trigger a heap out-of-bounds read in OpenSLP service resulting in a denial-of-service condition.

Frequently asked questions

What is CVE-2021-21995?: OpenSLP as used in ESXi has a denial-of-service vulnerability due a heap out-of-bounds read issue. A malicious actor with network access to port 427 on ESXi may be able to trigger a heap out-of-bounds read in OpenSLP service resulting in a denial-of-service condition.
How severe is CVE-2021-21995?: CVE-2021-21995 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-21995 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21995?: CVE-2021-21995 primarily affects Vmware Cloud Foundation. In total, 238 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-21995?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-21995 published?: CVE-2021-21995 was published on 2021-07-13 and last updated on 2026-06-17.

References

https://www.vmware.com/security/advisories/VMSA-2021-0014.html

Affected products (238)

cpe:2.3:a:vmware:cloud_foundation:*:*:*:*:*:*:*:*
cpe:2.3:o:vmware:cloud_foundation:*:*:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:-:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201701001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201703001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201703002:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201704001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707101:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707102:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707103:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707201:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707202:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707203:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707204:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707205:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707206:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707207:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707208:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707209:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707210:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707211:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707212:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707213:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707214:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707215:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707216:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707217:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707218:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707219:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707220:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201707221:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201710001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201712001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201803001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201806001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201808001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201810001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201810002:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201811001:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:6.5:650-201811002:*:*:*:*:*:*

More vulnerabilities in Vmware Cloud Foundation

CVE-2023-34063 — Critical (CVSS 9.9): Aria Automation contains a Missing Access Control vulnerability. An authenticated malicious actor may exploit this…
CVE-2024-38812 — Critical (CVSS 9.8): The vCenter Server contains a heap-overflow vulnerability in the implementation of the DCERPC protocol. A malicious…
CVE-2024-37079 — Critical (CVSS 9.8): vCenter Server contains a heap-overflow vulnerability in the implementation of the DCERPC protocol. A malicious actor…
CVE-2023-20864 — Critical (CVSS 9.8): VMware Aria Operations for Logs contains a deserialization vulnerability. An unauthenticated, malicious actor with…
CVE-2022-22972 — Critical (CVSS 9.8): VMware Workspace ONE Access, Identity Manager and vRealize Automation contain an authentication bypass vulnerability…
CVE-2022-22954 — Critical (CVSS 9.8): VMware Workspace ONE Access and Identity Manager contain a remote code execution vulnerability due to server-side…

All CVEs affecting Vmware Cloud Foundation →

Other CWE-125 (Out-of-bounds Read) vulnerabilities

CVE-2026-24826 — Critical (CVSS 10.0): Out-of-bounds Write, Divide By Zero, NULL Pointer Dereference, Use of Uninitialized Resource, Out-of-bounds Read,…
CVE-2024-22004 — Critical (CVSS 10.0): Due to length check, an attacker with privilege access on a Linux Nonsecure operating system can trigger a…
CVE-2021-41556 — Critical (CVSS 10.0): sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an out-of-bounds read (in the core interpreter) that…
CVE-2021-21777 — Critical (CVSS 10.0): An information disclosure vulnerability exists in the Ethernet/IP UDP handler functionality of EIP Stack Group OpENer…
CVE-2017-14451 — Critical (CVSS 10.0): An exploitable out-of-bounds read vulnerability exists in libevm (Ethereum Virtual Machine) of CPP-Ethereum. A…
CVE-2013-0767 — Critical (CVSS 10.0): The nsSVGPathElement::GetPathLengthScale function in Mozilla Firefox before 18.0, Firefox ESR 10.x before 10.0.12 and…

Browse all CWE-125 (Out-of-bounds Read) vulnerabilities →