CVE-2021-27436

mediumpriority · track · 24EPSS 0.007 · 53 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.71% (53rd) EPSS

CVSS 4.3 · medium

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cisa_csaf_ot · nvd

EPSS · scored 2026-10-27

WebAccess/SCADA Versions 9.0 and prior is vulnerable to cross-site scripting, which may allow an attacker to send malicious JavaScript code to an unsuspecting user, which could result in hijacking of the user’s cookie/session tokens, redirecting the user to a malicious webpage and performing unintended browser actions.

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 update to Version 9.0.1 or later.
https://www.advantech.com/support/details/manual?id=1-1J6QG9J

cvss

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

6.1

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

v3.05.4mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:R/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 (4)

Products and version ranges known to be affected.

WebAccess/SCADA: Versions 9.0 and priorall versionscisa_csaf_otUS
Advantech WebAccess/SCADA≤ 9.0cisa_csaf_otUS
n/a Advantech WebAccess/SCADA≤ Versions 9.0 and priorenisa_euvdEU
advantech webaccess/scada≤ 9.0nvdUScpe:2.3:a:advantech:webaccess\/scada:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-21-075-01Advantech WebAccess/SCADA2021-03-16icsa · cisa_csaf_otUS
Successful exploitation of this vulnerability could allow an unauthorized user to steal a user 's cookie/session token or redirect an authorized user to a malicious webpage.

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 2021-03-18modified 2026-06-17

related (53,021)

Related entries.

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Roundcube Webmail before 1.5.12 and 1.6 before 1.6.12 is prone to a Cross-Site-Scripting (XSS) vulnerability via the animate tag in an SVG document.
CVE-2025-48700US	—OT critical	1.71% (77th)	KEV	2025-06-23
An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0 and 10.0 and 10.1. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to exec…
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+53016 more

references (6)

External citations — patches, advisories, analysis.

scry

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