CVE-2021-21941Public exploitNetwork attack vector

Remote code execution via thread-context race

Published Oct 12, 2021 · Updated Aug 3, 2024

Use-after-free in Anker Innovations eufy HomeBase 2 2.1.6.9h allows remote attackers to execute code via crafted TCP packets. CreatePushThread passes the same zx_push_stream_ctx allocation as the pthread handle and thread argument; receive_push_thread can free it before pthread_create writes the thread ID. Unauthenticated access to TCP port 9000 and winning the race through heap spraying are required, and successful exploitation runs attacker-controlled code on the appliance.

CVSS severity10.0
Critical
EPSS probability1.68%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Anker Innovations eufy HomeBase 2 2.1.6.9h allows remote attackers to execute code via crafted TCP packets. CreatePushThread passes the same zx_push_stream_ctx allocation as the pthread handle and thread argument; receive_push_thread can free it before pthread_create writes the thread ID. Unauthenticated access to TCP port 9000 and winning the race through heap spraying are required, and successful exploitation runs attacker-controlled code on the appliance.

The record

CVE
CVE-2021-21941
Published
Oct 12, 2021
Updated
Aug 3, 2024
Vendor
Anker Innovations
Product
eufy HomeBase 2
Classifications
CWE-368, T1210
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 12, 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?

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

  1. Affected versionversion=Anker Eufy Homebase 2 2.1.6.9h

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Anker Innovations · eufy HomeBase 2version=Anker Eufy Homebase 2 2.1.6.9h

Published CVSS scores

10.0Cisco TalosCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-368Context Switching Race Condition
T1210Exploitation of Remote Services

Public exploit references

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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