CVE-2021-22019Network attack vector

Service interruption via crafted JSON-RPC message

Published Sep 23, 2021 · Updated Aug 3, 2024

Denial of service in VMware vCenter Server before 7.0 U2c allows remote attackers to interrupt VAPI through port 5480. VAPI accepts a specially crafted JSON-RPC message, but VMware has not disclosed the exact processing error that triggers the denial of service. Network access to port 5480 is required; affected branches are vCenter Server 7.x before 7.0 U2c, 6.7 before 6.7 U3o, and 6.5 before 6.5 U3q, plus Cloud Foundation 4.x before 4.3 and 3.x before 3.10.2.2.

CVSS severity5.3
Medium
EPSS probability1.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in VMware vCenter Server before 7.0 U2c allows remote attackers to interrupt VAPI through port 5480. VAPI accepts a specially crafted JSON-RPC message, but VMware has not disclosed the exact processing error that triggers the denial of service. Network access to port 5480 is required; affected branches are vCenter Server 7.x before 7.0 U2c, 6.7 before 6.7 U3o, and 6.5 before 6.5 U3q, plus Cloud Foundation 4.x before 4.3 and 3.x before 3.10.2.2.

The record

CVE
CVE-2021-22019
Published
Sep 23, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
5.3VMwareCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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