CVE-2021-21974

mediumpriority · attend · 61EPSS 0.451 · 99 %ileexploit · PoCEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

7 exploits · PoC

Likely / severe?

45.1% (99th) EPSS

CVSS 5.8 · medium

Is it mine?

13 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-25

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

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

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–8.8

v2.05.8mediumAV:A/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 6.5 · impact 6.4

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.9

v3.18.8highAV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondaryexploitability 2.8 · impact 5.9

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-787USprimaryCWE-122US

exploits (7)

Public proof-of-concept and weaponised exploit code.

Aiyakami/CVE-2021-21974自研针对ESXI 堆栈溢出的CVE-2021-21974 POC，只支持项目给出的的目标和环境，用于学习和研究PoC · poc_in_github
CYBERTHREATANALYSIS/ESXi-Ransomware-Scanner-miESXi EZ - A custom scanner that takes list of IPs either in JSON, CSV or individually and checks for infection CVE-2021-21974PoC · poc_in_github
Shadow0ps/CVE-2021-21974POC for CVE-2021-21974 VMWare ESXi RCE ExploitPoC · poc_in_github
abirasecurity/CVE-2021-21974_vuln_dectectionCVE-2021-21974 Vulnerability Detection Tool Safe PoC that identifies vulnerable SLP implementations without exploitationPoC · poc_in_github
hateme021202/cve-2021-21974Nmap NSE script for cve-2021-21974PoC · poc_in_github
mercylessghost/CVE-2021-21974mercylessghost/CVE-2021-21974PoC · poc_in_github

affected products (13)

Products and version ranges known to be affected.

n/a VMware Cloud Foundation≤ 4.x before 4.2 and 3.xenisa_euvdEU
n/a VMware ESXi≤ 6.7 before ESXi670-202102401-SGenisa_euvdEU
n/a VMware ESXi≤ 6.5 before ESXi650-202102101-SGenisa_euvdEU
n/a VMware ESXi≤ 7.0 before ESXi70U1c-17325551enisa_euvdEU
Broadcom Inc. VMware Cloud Foundation4.0 → 4.2fstec_bduRU
Broadcom Inc. VMware ESXi6.5 → ESXi650-202102101-SGfstec_bduRU
Broadcom Inc. VMware ESXi6.7 → ESXi670-202102401-SGfstec_bduRU
Broadcom Inc. VMware ESXi7.0 → ESXi70U1c-17325551fstec_bduRU
vmware cloud foundation3.0 → 3.10.1.2nvdUScpe:2.3:a:vmware:cloud_foundation:*:*:*:*:*:*:*:*
vmware cloud foundation4.0 → 4.2nvdUScpe:2.3:a:vmware:cloud_foundation:*:*:*:*:*:*:*:*
vmware esxi= 6.5nvdUScpe:2.3:o:vmware:esxi:*:*:*:*:*:*:*:*
vmware esxi= 6.7nvdUScpe:2.3:o:vmware:esxi:*:*:*:*:*:*:*:*
vmware esxi= 7.0.0nvdUScpe:2.3:o:vmware:esxi:*:*:*:*:*:*:*:*

also known as (4)

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 2021-02-24modified 2026-06-17

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+16035 more

references (14)

External citations — patches, advisories, analysis.

scry

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