CVE-2021-26638

Household-head takeover via authentication-result tampering

Published Jun 22, 2022 · Updated Aug 3, 2024

Improper authentication in Xi S&D Inc. S&D SmartHome (SmartCare) 3.2.48 and earlier allows remote attackers to seize household-head access. The server fails to validate the resident-authentication result, allowing a modified result in the local Android app to be accepted. Exploitation requires tampering with that client-side result and permits exposure of household information and control of lighting, heating, and other indoor functions.

CVSS severity7.3
High
EPSS probability3.70%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in Xi S&D Inc. S&D SmartHome (SmartCare) 3.2.48 and earlier allows remote attackers to seize household-head access. The server fails to validate the resident-authentication result, allowing a modified result in the local Android app to be accepted. Exploitation requires tampering with that client-side result and permits exposure of household information and control of lighting, heating, and other indoor functions.

The record

CVE
CVE-2021-26638
Published
Jun 22, 2022
Updated
Aug 3, 2024
Vendor
Xi S&D Inc.
Product
S&D SmartHome (SmartCare)
Classifications
CWE-287
Attack vector
adjacent
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 22, 2022CVE 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <=3.2.48

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesauthenticated

What is affected?

Xi S&D Inc. · S&D SmartHome (SmartCare)version=unspecified <=3.2.48

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10.0NIST NVDAV:N/AC:L/Au:N/C:C/I:C/A:C
7.3KrCERT/CCCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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