How severe is CVE-2021-22291?

CVE-2021-22291 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-22291 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2021-22291?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2021-22291 have an EU (EUVD) identifier?

Yes. CVE-2021-22291 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-9437.

When was CVE-2021-22291 published?

CVE-2021-22291 was published on 2025-10-07 and last updated on 2026-06-17.

CVE-2021-22291

CVE-2021-22291 is a high-severity vulnerability with a CVSS 3.x base score of 8.0. 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: High (CVSS 3.x base score 8.0)
CVSS v4: 8.5
EPSS exploit prediction: 0% (22nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-9437
Weakness: CWE-79
Published: 2025-10-07
Last modified: 2026-06-17

Description

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in ABB EIBPORT V3 KNX, ABB EIBPORT V3 KNX GSM.This issue affects EIBPORT V3 KNX: before 3.9.2; EIBPORT V3 KNX GSM: before 3.9.2.

Frequently asked questions

What is CVE-2021-22291?: Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in ABB EIBPORT V3 KNX, ABB EIBPORT V3 KNX GSM.This issue affects EIBPORT V3 KNX: before 3.9.2; EIBPORT V3 KNX GSM: before 3.9.2.
How severe is CVE-2021-22291?: CVE-2021-22291 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-22291 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2021-22291?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2021-22291 have an EU (EUVD) identifier?: Yes. CVE-2021-22291 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-9437.
When was CVE-2021-22291 published?: CVE-2021-22291 was published on 2025-10-07 and last updated on 2026-06-17.

References

https://search.abb.com/library/Download.aspx?DocumentID=9AKK108471A7808&LanguageCode=en&DocumentPartId=pdf&Action=Launch

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