How severe is CVE-2021-22676?

CVE-2021-22676 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-22676 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22676?

CVE-2021-22676 affects Advantech Webaccess/scada. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-22676?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-22676 published?

CVE-2021-22676 was published on 2021-08-10 and last updated on 2026-06-17.

CVE-2021-22676

CVE-2021-22676 is a medium-severity vulnerability in Advantech Webaccess/scada with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Advantech Webaccess/scada
Published: 2021-08-10
Last modified: 2026-06-17

Description

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).

Frequently asked questions

What is CVE-2021-22676?: 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).
How severe is CVE-2021-22676?: CVE-2021-22676 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-22676 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22676?: CVE-2021-22676 affects Advantech Webaccess/scada. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-22676?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-22676 published?: CVE-2021-22676 was published on 2021-08-10 and last updated on 2026-06-17.

References

https://us-cert.cisa.gov/ics/advisories/icsa-21-217-04

Affected products (1)

cpe:2.3:a:advantech:webaccess\/scada:*:*:*:*:*:*:*:*

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