CVE-2026-7643Public exploitNetwork attack vector

Cross-origin API access via wildcard CORS headers

Published May 2, 2026 · Updated May 2, 2026

Permissive CORS in ChatGPTNextWeb NextChat 2.16.0 through 2.16.1 allows remote attackers to read API responses via malicious sites. The Next.js headers configuration assigns wildcard origins, methods, and request headers to every /api/* route, allowing cross-origin use of x-base-url to choose the proxy destination. Exploitation requires a user to visit attacker-controlled content and a non-static deployment; exposed responses can disclose configuration or server API keys.

CVSS severity4.3
Medium
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

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Summary

What happened

Permissive CORS in ChatGPTNextWeb NextChat 2.16.0 through 2.16.1 allows remote attackers to read API responses via malicious sites. The Next.js headers configuration assigns wildcard origins, methods, and request headers to every /api/* route, allowing cross-origin use of x-base-url to choose the proxy destination. Exploitation requires a user to visit attacker-controlled content and a non-static deployment; exposed responses can disclose configuration or server API keys.

The record

CVE
CVE-2026-7643
Published
May 2, 2026
Updated
May 2, 2026
Vendor
ChatGPTNextWeb
Product
NextChat
Classifications
CWE-346, CWE-942, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 2, 2026CVE publishedPublication date reported by the CVE source.
  2. May 2, 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=2.16.0
  2. Affected versionversion=2.16.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ChatGPTNextWeb · NextChatversion=2.16.0; version=2.16.1

Published CVSS scores

2.1VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
5.0VulDBAV:N/AC:L/Au:N/C:N/I:P/A:N
4.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/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-346Origin Validation Error
CWE-942Permissive Cross-domain Security Policy with Untrusted Domains
T1189Drive-by Compromise

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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