CVE-2021-22291Network attack vector

Session hijacking via reflected cross-site scripting

Published Oct 7, 2025 · Updated Oct 7, 2025

Reflected XSS in ABB EIBPORT V3 KNX and KNX GSM before 3.9.2 allows remote authenticated users to obtain a victim session ID. ABB states that vulnerable firmware fails to maintain secure session management, but it does not identify the reflected input endpoint or parameter. Low privileges and active victim interaction are required; the copied session ID permits unauthenticated device access and configuration changes.

CVSS severity8.5
High
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in ABB EIBPORT V3 KNX and KNX GSM before 3.9.2 allows remote authenticated users to obtain a victim session ID. ABB states that vulnerable firmware fails to maintain secure session management, but it does not identify the reflected input endpoint or parameter. Low privileges and active victim interaction are required; the copied session ID permits unauthenticated device access and configuration changes.

The record

CVE
CVE-2021-22291
Published
Oct 7, 2025
Updated
Oct 7, 2025
Vendor
GENEREX SYSTEMS Computervertriebsgesellschaft mbH
Product
EIBPORT V3 KNX GSM
Classifications
CWE-79, T1539
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 7, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 7, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <3.9.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

GENEREX SYSTEMS Computervertriebsgesellschaft mbH · EIBPORT V3 KNX GSMversion=0 <3.9.2
GENEREX SYSTEMS Computervertriebsgesellschaft mbH · EIBPORT V3 KNXversion=0 <3.9.2

Published CVSS scores

8.0ABBCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
8.5ABBCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1539Steal Web Session Cookie

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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