CVE-2025-50733Public exploitNetwork attack vector

Browser code execution via unsanitized HTML preview

Published Aug 22, 2025 · Updated Aug 26, 2025

Cross-site scripting in NextChat's HTMLPreview component allows remote attackers to execute JavaScript through a crafted AI response. HTMLPreview places user-influenced response HTML into an iframe that permits scripts without first sanitizing the content. Execution requires a user to open the generated HTML preview, exposing browser-stored secrets and allowing actions in that user's session.

CVSS severity6.1
Medium
EPSS probability0.20%
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 NextChat's HTMLPreview component allows remote attackers to execute JavaScript through a crafted AI response. HTMLPreview places user-influenced response HTML into an iframe that permits scripts without first sanitizing the content. Execution requires a user to open the generated HTML preview, exposing browser-stored secrets and allowing actions in that user's session.

The record

CVE
CVE-2025-50733
Published
Aug 22, 2025
Updated
Aug 26, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 22, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.1CISA ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A: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.

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

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript/JScript

Public exploit references

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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