CVE-2021-21985 CISA KEV · Actively exploitedLinked to ransomwareSuited to automated attack · CISA

Vulnerability in N/a VMware vCenter Server And VMware Cloud Foundation

CVSS score

9.8

EPSS probability

%100.0

Risk score

19.6

Published

5 y ago

Overview Public Exploits (0)Newsroom Vulnerability Timeline

Mitigation available

Apply updates per vendor instructions.

Impact on My Inventory

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Vulnerability description

DayBreach CVE AI Research

CVE-2021-21985 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

The vSphere Client (HTML5) contains a remote code execution vulnerability due to lack of input validation in the Virtual SAN Health Check plug-in which is enabled by default in vCenter Server. A malicious actor with network access to port 443 may exploit this issue to execute commands with unrestricted privileges on the underlying operating system that hosts vCenter Server.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2021-21985 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

ID	VENDOR	PRODUCT	ACTION
1	n/a	VMware vCenter Server and VMware Cloud Foundation	View
2	vmware	vCenter Server	View
3	vmware	vCenter Server	View
4	vmware	vCenter Server	View
5	vmware	cloud foundation	View
6	vmware	cloud foundation	View

Total affected vendors: 2|Products: 6

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCORE	VERSION	SEVERITY	VECTOR	SOURCE
10.0	CVSS V2	—	AV:N/AC:L/Au:N/C:C/I:C/A:C	NVD
9.8	CVSS V3_1	CRITICAL	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	CVE ADP
9.8	CVSS V31	CRITICAL	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD

Patch and Remediation Guide

Solution & Remediation Advisory

Workaround

Resmî yama doğrulanamadı; geçici azaltım veya workaround mevcut.

canonical

Apply updates per vendor instructions.

Confirm the affected product and version against the source evidence above.

Restrict access to internet-facing services and apply network segmentation.

Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.

Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

This CVE is marked as actively exploited in the CISA KEV catalogue, but no verified, downloadable public PoC or Metasploit module has been found yet. Evidence of active exploitation does not mean that public exploit code exists.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-21985 is associated with the following CWEs:

CWE-918: Server-Side Request Forgery (SSRF)CWE-20: Improper Input Validation CWE-470: Common Weakness Enumeration Entry CWE-470

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-21985 weaknesses.

CAPEC-66: SQL Injection CAPEC-126: Path Traversal CAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden

PermissionsGerekmiyor

UserGerekmiyor

Official Sources and Advisories

https://www.vmware.com/security/advisories/VMSA-2021-0010.htmlvendor-advisory http://packetstormsecurity.com/files/162812/VMware-Security-Advisory-2021-0010.htmlvendor-advisory http://packetstormsecurity.com/files/163487/VMware-vCenter-Server-Virtual-SAN-Health-Check-Remote-Code-Execution.htmlvendor-advisory https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21985nvd CISA Known Exploited Vulnerabilities Catalogkev

CVSS Vector Radar Chart

9.8 / 10

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone required

User InteractionNone required

Confidentiality (Gizlilik)Low

Integrity (Bütünlük)None

Availability (Erişilebilirlik)High

Geçici çözüm

Resmî yama doğrulanamadı; geçici azaltım veya workaround mevcut.

Follow the vendor

n/a

vmware

Weakness Type (CWE & CAPEC)

CWE-918 CWE-20 CWE-470

Similar Vulnerabilities

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CVE-2015-3306 Actively exploited

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