CVE-2021-31642

Name: CVE-2021-31642
Creator: NVD / NIST
Published: 2021-06-01T15:15:07.717+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 43.67%

Last modified Jun 17, 2026

CVE-2021-31642 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. A denial of service condition exists after an integer overflow in several IoT devices from CHIYU Technology, including BIOSENSE, Webpass, and BF-630, BF-631, and SEMAC. The vulnerability can be explored by sending an unexpected integer (> 32 bits) on the page parameter that will crash the web portal and making it unavailable until a reboot of the device.. EPSS estimates a 43.67% chance of exploitation in the next 30 days.

Description

A denial of service condition exists after an integer overflow in several IoT devices from CHIYU Technology, including BIOSENSE, Webpass, and BF-630, BF-631, and SEMAC. The vulnerability can be explored by sending an unexpected integer (> 32 bits) on the page parameter that will crash the web portal and making it unavailable until a reboot of the device.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

43.67%

98.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-190

Affected Software

Vendor	Product	Versions
Chiyu-Tech	Semac S2 Firmware	All versions
Chiyu-Tech	Semac D1 Firmware	All versions
Chiyu-Tech	Semac D2 Firmware	All versions
Chiyu-Tech	Semac D4 Firmware	All versions
Chiyu-Tech	Semac S3v3 Firmware	All versions
Chiyu-Tech	Semac D2 N300 Firmware	All versions
Chiyu-Tech	Semac S1 Osdp Firmware	All versions
Chiyu-Tech	Bf-631 Firmware	All versions
Chiyu-Tech	Bf-630 Firmware	All versions
Chiyu-Tech	Webpass Firmware	All versions
Chiyu-Tech	Biosense Firmware	All versions

References

http://packetstormsecurity.com/files/162934/CHIYU-IoT-Denial-Of-Service.htmlExploit, Third Party Advisory, VDB Entry
https://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31642Exploit, Third Party Advisory
https://seguranca-informatica.pt/dancing-in-the-iot-chiyu-devices-vulnerable-to-remote-attacks/Exploit, Third Party Advisory
https://www.chiyu-tech.com/msg/message-Firmware-update-87.htmlVendor Advisory
http://packetstormsecurity.com/files/162934/CHIYU-IoT-Denial-Of-Service.htmlExploit, Third Party Advisory, VDB Entry
https://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31642Exploit, Third Party Advisory
https://seguranca-informatica.pt/dancing-in-the-iot-chiyu-devices-vulnerable-to-remote-attacks/Exploit, Third Party Advisory
https://www.chiyu-tech.com/msg/message-Firmware-update-87.htmlVendor Advisory

Timeline

Published: Jun 1, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-31642?

How severe is CVE-2021-31642?

CVE-2021-31642 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 43.67% probability of exploitation in the next 30 days.

How do I fix CVE-2021-31642?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-31642?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST