CVE-2021-27289 (CVSS 9.1)

Description

A replay attack vulnerability was discovered in a Zigbee smart home kit manufactured by Ksix (Zigbee Gateway Module = v1.0.3, Door Sensor = v1.0.7, Motion Sensor = v1.0.12), where the Zigbee anti-replay mechanism - based on the frame counter field - is improperly implemented. As a result, an attacker within wireless range can resend captured packets with a higher sequence number, which the devices incorrectly accept as legitimate messages. This allows spoofed commands to be injected without authentication, triggering false alerts and misleading the user through notifications in the mobile application used to monitor the network.

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CVSS v3.1 Score

9.1

CRITICAL

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

Weakness Type (CWE)

CWE-294 CWE-294

References

Other References

https://github.com/TheMalwareGuardian/CVE-2021-27289 https://packetstormsecurity.com/files/160331/Ksix-Zigbee-Devices-Playback-Protection-Bypass.html https://www.exploit-db.com/exploits/49169 https://www.youtube.com/watch?v=5IFUpRKEioA https://www.youtube.com/watch?v=XFOy3wSlC9Q https://www.youtube.com/watch?v=yc9IEt5IMmA

Frequently Asked Questions

What is CVE-2021-27289? +

A replay attack vulnerability was discovered in a Zigbee smart home kit manufactured by Ksix (Zigbee Gateway Module = v1.0.3, Door Sensor = v1.0.7, Motion Sensor = v1.0.12), where the Zigbee anti-replay mechanism - based on the frame counter field - is improperly implemented. As a result, an attacker within wireless range can resend captured packets with a higher sequence number, which the devices incorrectly accept as legitimate messages. This allows spoofed commands to be injected without authentication, triggering false alerts and misleading the user through notifications in the mobile application used to monitor the network. It has a CVSS v3.1 base score of 9.1 (CRITICAL).

How severe is CVE-2021-27289? +

CVE-2021-27289 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

How do I check if I'm vulnerable to CVE-2021-27289? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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