CVE-2021-22676

mediumpriority · track · 24EPSS 0.006 · 51 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.64% (51st) EPSS

CVSS 4.3 · medium

Is it mine?

7 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cisa_csaf_ot · nvd

EPSS · scored 2026-10-27

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).

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

No vendor fix yet; a mitigation is available.

MitigationWebAccess/SCADAcisa_csaf_ot
Advantech recommends users running version 8 of the software to update to Version 8.4.5
https://www.advantech.tw/support/details/installation?id=1-MS9MJV

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.06.5mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Nsecondary · CISA US

v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimaryCWE-79US

affected products (7)

Products and version ranges known to be affected.

WebAccess/SCADA: versions prior to 8.4.5all versionscisa_csaf_otUS
WebAccess/SCADA: versions prior to 9.0.1all versionscisa_csaf_otUS
Advantech WebAccess/SCADA< 8.4.5cisa_csaf_otUS
Advantech WebAccess/SCADA< 9.0.1cisa_csaf_otUS
n/a WebAccess/SCADA≤ WebAccess/SCADA versions prior to 8.4.5, WebAccess/SCADA versions prior to 9.0.1enisa_euvdEU
advantech webaccess/scada< 8.4.5nvdUScpe:2.3:a:advantech:webaccess\/scada:*:*:*:*:*:*:*:*
advantech webaccess/scada9.0 → 9.0.1nvdUScpe:2.3:a:advantech:webaccess\/scada:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-21-217-04Advantech WebAccess SCADA2021-08-05icsa · cisa_csaf_otUS
Successful exploitation of these vulnerabilities could allow an attacker to hijack a user 's cookie/session tokens, gain unauthorized access to files and directories, and execute arbitrary code.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cisa_csaf_ot nvd NVD CVE.org MITRE

published 2021-08-10modified 2026-06-17

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+53058 more

references (6)

External citations — patches, advisories, analysis.

scry

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