Dell EMC PowerFlex, v3.5.x contain a Cross-Site WebSocket Hijacking Vulnerability in the Presentation Server/WebUI.

published 2021-07-12 5y ago modified 2026-06-17 4mo ago also EUVD-2021-8860

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 27%
public exploits: 0; none known

Dell EMC PowerFlex, v3.5.x contain a Cross-Site WebSocket Hijacking Vulnerability in the Presentation Server/WebUI. An unauthenticated attacker could potentially exploit this vulnerability by tricking the user into performing unwanted actions on the Presentation Server and perform which may lead to configuration changes.

Patch / fix

fixed in 1

dell powerflex_presentation_server 3.6

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Exploit prediction

0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
NVD	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected products

Dell PowerFlex

Classification

Weakness

CWE-345 Insufficient Verification of Data Authenticity

References

dell.com /support/kbdoc/000189265
vendor-advisory

Sources

CVE List CVE-2021-21588
NVD CVE-2021-21588

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