CVE-2021-31643

Name: CVE-2021-31643
Creator: NVD / NIST
Published: 2021-06-01T15:15:07.747+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 88.45%

Last modified Jun 17, 2026

CVE-2021-31643 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. An XSS vulnerability exists in several IoT devices from CHIYU Technology, including SEMAC, Biosense, BF-630, BF-631, and Webpass due to a lack of sanitization on the component if.cgi - username parameter.. EPSS estimates a 88.45% chance of exploitation in the next 30 days.

Description

An XSS vulnerability exists in several IoT devices from CHIYU Technology, including SEMAC, Biosense, BF-630, BF-631, and Webpass due to a lack of sanitization on the component if.cgi - username parameter.

Metrics

CVSS 3.1

5.4/10

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

EPSS Probability

88.45%

99.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Chiyu-Tech	Bf-631 Firmware	All versions
Chiyu-Tech	Bf-630 Firmware	All 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	Webpass Firmware	All versions
Chiyu-Tech	Biosense Firmware	All versions

References

http://packetstormsecurity.com/files/162887/CHIYU-IoT-Cross-Site-Scripting.htmlExploit, Third Party Advisory, VDB Entry
https://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31643Exploit, 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/162887/CHIYU-IoT-Cross-Site-Scripting.htmlExploit, Third Party Advisory, VDB Entry
https://gitbook.seguranca-informatica.pt/cve-and-exploits/cves/chiyu-iot-devices#cve-2021-31643Exploit, 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-2021-31643?

How severe is CVE-2021-31643?

CVE-2021-31643 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 88.45% probability of exploitation in the next 30 days.

How do I fix CVE-2021-31643?

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-2021-31643?

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

Scan your code now

Source: NVD / NIST