CVE-2026-66636Network attack vector

Contributor script execution via undisclosed input

Published Aug 18, 2026 · Updated Aug 18, 2026

Cross-site scripting in Kainex Wise Chat 3.4 and earlier allows remote authenticated users to execute script in a victim browser. Patchstack and NVD describe the issue only as contributor-level XSS and do not disclose the vulnerable endpoint, parameter, or rendering path, so the specific component that emits untrusted content remains unknown. Exploitation requires contributor access and a victim to view the tainted chat content; published records describe browser-side script execution in the site's origin, not server-side code execution or plugin takeover.

CVSS severity6.5
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Kainex Wise Chat 3.4 and earlier allows remote authenticated users to execute script in a victim browser. Patchstack and NVD describe the issue only as contributor-level XSS and do not disclose the vulnerable endpoint, parameter, or rendering path, so the specific component that emits untrusted content remains unknown. Exploitation requires contributor access and a victim to view the tainted chat content; published records describe browser-side script execution in the site's origin, not server-side code execution or plugin takeover.

The record

CVE
CVE-2026-66636
Published
Aug 18, 2026
Updated
Aug 18, 2026
Vendor
Marcin Ławrowski
Product
Wise Chat
Classifications
CWE-79, T1189
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 18, 2026Record 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=n/a <=3.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Marcin Ławrowski · Wise Chatversion=n/a <=3.4

Published CVSS scores

6.5PatchstackCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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')
T1189Drive-by Compromise

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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