Skip to content
Fencer Vulns
medium 6.1

CVE-2021-22676 json

UserExcelOut.asp within WebAccess/SCADA is vulnerable to cross-site scripting (XSS), which could allow an attacker to send malicious JavaSc…

published 2021-08-10 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-9812

cvss
6.1
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 51%
public exploits
0
none known

Summary

UserExcelOut.asp within WebAccess/SCADA is vulnerable to cross-site scripting (XSS), which could allow an attacker to send malicious JavaScript code. This could result in hijacking of cookie/session tokens, redirection to a malicious webpage, and unintended browser action on the WebAccess/SCADA (WebAccess/SCADA versions prior to 8.4.5, WebAccess/SCADA versions prior to 9.0.1).

Patch / fix

  • advantech webaccess/scada 8.4.5, 9.0.1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-21-217-04 updated cvss 6.5

Advantech WebAccess SCADA

  • Advantech WebAccess/SCADA < 9.0.1, < 8.4.5
    affected: mitigation “Advantech recommends users running version 8 of the software to update to Version 8.4.5” advantech.tw

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

Exploit prediction

0.64% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected products

  • n/a WebAccess/SCADA

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.