CVE-2021-22737Network attack vector

Unauthorized access via unrestricted authentication attempts

Published May 26, 2021 · Updated Aug 3, 2024

Improper authentication restrictions in Schneider Electric homeLYnk and spaceLYnk 2.60 and earlier allow remote attackers to gain unauthorized access. The products do not sufficiently restrict repeated authentication attempts, allowing credentials to be discovered through brute-force guessing. No prior privileges or user interaction are required, but network access and successful credential guessing are necessary to access product functions.

CVSS severity5.6
Medium
EPSS probability0.95%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication restrictions in Schneider Electric homeLYnk and spaceLYnk 2.60 and earlier allow remote attackers to gain unauthorized access. The products do not sufficiently restrict repeated authentication attempts, allowing credentials to be discovered through brute-force guessing. No prior privileges or user interaction are required, but network access and successful credential guessing are necessary to access product functions.

The record

CVE
CVE-2021-22737
Published
May 26, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-307, T1110.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 26, 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

5.6Schneider ElectricCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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

CWE-307Improper Restriction of Excessive Authentication Attempts
T1110.001Password Guessing

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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