Is CVE-2021-22764 in the CISA KEV catalog?

No. CVE-2021-22764 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2021-22764?

CVE-2021-22764 has a CVSS v3 base score of 5.3 (MEDIUM).

What is the EPSS score for CVE-2021-22764?

CVE-2021-22764 has an EPSS score of 1.86% (77th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2021-22764?

Upgrade powerlogic pm5560 firmware to 2.7.8 or later. Fixes are available for 3 affected products.

CVE & CISA-KEV Catalog

CVE-2021-22764

MEDIUMEPSS 77th pctl

5.3

CVSS v3

NVD

Description

A CWE-287: Improper Authentication vulnerability exists in PowerLogic PM55xx, PowerLogic PM8ECC, PowerLogic EGX100 and PowerLogic EGX300 (see security notification for version infromation) that could cause loss of connectivity to the device via Modbus TCP protocol when an attacker sends a specially crafted HTTP request.

CWE-287Improper Authentication

How to fix

Remediation Available

powerlogic pm5560 firmwareNVD

Affected:< 2.7.8Fixed in:2.7.8CVE-2021-22764derived from NVD

powerlogic pm5561 firmwareNVD

Affected:< 10.7.3Fixed in:10.7.3CVE-2021-22764derived from NVD

powerlogic pm5563 firmwareNVD

Affected:< 2.7.8Fixed in:2.7.8CVE-2021-22764derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityLow

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

Exploit Intelligence

1.86%probability of exploitation in 30 days

77thpercentile

Elevated risk: more likely to be exploited than 77% of all known CVEs.

References

Other references2

Related Vulnerabilities

Other CWE-287 (Improper Authentication) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2023-35082	Critical	9.8	100%	KEV + Ransom	Fix
CVE-2023-35078	Critical	9.8	100%	KEV + Ransom	Fix
CVE-2017-7921	Critical	9.8	100%	KEV	-
CVE-2024-7593	Critical	9.8	100%	KEV	-
CVE-2023-46805	High	8.2	100%	KEV + Ransom	-
CVE-2022-40684	Critical	9.8	100%	KEV + Ransom	Fix

Embed a live status badge for CVE-2021-22764

Markdown

[![CVE-2021-22764](https://tridentstack.com/cve/badge/CVE-2021-22764.svg)](https://tridentstack.com/cve/CVE-2021-22764)

HTML

<a href="https://tridentstack.com/cve/CVE-2021-22764"><img src="https://tridentstack.com/cve/badge/CVE-2021-22764.svg" alt="CVE-2021-22764"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-29.