CVE-2021-34540

Name: CVE-2021-34540
Creator: NVD / NIST
Published: 2021-06-11T12:15:12.13+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 0.87%

Last modified Jun 17, 2026

CVE-2021-34540 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. Advantech WebAccess 8.4.2 and 8.4.4 allows XSS via the username column of the bwRoot.asp page of WADashboard.. EPSS estimates a 0.87% chance of exploitation in the next 30 days.

Description

Advantech WebAccess 8.4.2 and 8.4.4 allows XSS via the username column of the bwRoot.asp page of WADashboard.

Metrics

CVSS 3.1

6.1/10

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

EPSS Probability

0.87%

54.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Advantech	Webaccess	8.4.2
Advantech	Webaccess	8.4.4

References

https://github.com/ethancsyang/CveProject/tree/main/CVE-2021-34540Exploit, Third Party Advisory
https://www.advantech.com/supportVendor Advisory
https://github.com/ethancsyang/CveProject/tree/main/CVE-2021-34540Exploit, Third Party Advisory
https://www.advantech.com/supportVendor Advisory

Timeline

Published: Jun 11, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-34540?

Advantech WebAccess 8.4.2 and 8.4.4 allows XSS via the username column of the bwRoot.asp page of WADashboard.

How severe is CVE-2021-34540?

CVE-2021-34540 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 0.87% probability of exploitation in the next 30 days.

How do I fix CVE-2021-34540?

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-2021-34540?

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

Scan your code now

Source: NVD / NIST