CVE-2021-21995

mediumpriority · track · 30EPSS 0.010 · 61 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.96% (61st) EPSS

CVSS 5 · medium

Is it mine?

11 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-125USprimaryCWE-125US

affected products (11)

Products and version ranges known to be affected.

n/a VMware ESXi and VMware Cloud Foundation≤ VMware ESXi(7.0 before ESXi70U2-17630552, 6.7 before ESXi670-202103101-SG, 6.5 before ESXi650-202107401-SG) and VMware Cloud Foundation (4.x, 3.x before 3.10.2)enisa_euvdEU
Broadcom Inc. VMware Cloud Foundation3.0.0 → 3.10.2fstec_bduRU
Broadcom Inc. VMware Cloud Foundation4.0 → 4.2.1fstec_bduRU
Broadcom Inc. VMware ESXi6.5 → ESXi650-202107401-SGfstec_bduRU
Broadcom Inc. VMware ESXi6.7 → ESXi670-202103101-SGfstec_bduRU
Broadcom Inc. VMware ESXi7.0 → ESXi70U2-17630552fstec_bduRU
vmware cloud foundation3.0 → 3.10.2nvdUScpe:2.3:a:vmware:cloud_foundation:*:*:*:*:*:*:*:*
vmware cloud foundation4.0 → 4.3nvdUScpe:2.3:o:vmware:cloud_foundation:*:*:*:*:*:*:*:*
vmware esxi= 6.5nvdUScpe:2.3:o:vmware:esxi:*:*:*:*:*:*:*:*
vmware esxi= 6.7nvdUScpe:2.3:o:vmware:esxi:*:*:*:*:*:*:*:*
vmware esxi= 7.0nvdUScpe:2.3:o:vmware:esxi:*:*:*:*:*:*:*:*

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-07-13modified 2026-06-17

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+11867 more

references (9)

External citations — patches, advisories, analysis.

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