CVE-2026-7177: ChatGPTNextWeb NextChat SSRF Vulnerability

CVE-2026-7177 Overview

A Server-Side Request Forgery (SSRF) vulnerability has been discovered in ChatGPTNextWeb NextChat up to version 2.16.1. The vulnerability exists in the proxyHandler function within the file app/api/[provider]/[...path]/route.ts, which fails to properly validate and sanitize user-controlled URLs before making server-side HTTP requests. This flaw allows remote attackers to manipulate the server into making arbitrary requests to internal or external resources.

Critical Impact

Attackers can exploit this SSRF vulnerability to access internal services, bypass network security controls, scan internal infrastructure, and potentially exfiltrate sensitive data from systems not directly accessible from the internet.

Affected Products

• ChatGPTNextWeb NextChat versions up to and including 2.16.1

Discovery Timeline

• 2026-04-27 - CVE-2026-7177 published to NVD
• 2026-04-29 - Last updated in NVD database

Technical Details for CVE-2026-7177

Vulnerability Analysis

This vulnerability is classified as CWE-918: Server-Side Request Forgery (SSRF). The proxyHandler function in NextChat's API routing system processes requests that include user-supplied URL parameters without adequate validation. When the application receives a request through the [provider]/[...path] API endpoint, it constructs and executes an HTTP request to the destination specified by the user input.

The lack of URL allowlist validation means attackers can craft malicious requests that cause the server to interact with arbitrary network resources. This includes the ability to probe internal network addresses (such as 127.0.0.1, localhost, or private IP ranges like 10.x.x.x, 192.168.x.x), cloud metadata endpoints (e.g., 169.254.169.254), and other services that would normally be inaccessible from external networks.

The exploit for this vulnerability has been publicly disclosed, increasing the risk of active exploitation against unpatched instances.

Root Cause

The root cause of this vulnerability lies in insufficient input validation within the proxyHandler function. The code accepts URL parameters from user requests and forwards them to make server-side HTTP calls without implementing proper restrictions. Specifically, the application fails to:

1. Validate that destination URLs are on an approved allowlist
2. Block requests to private/internal IP address ranges
3. Prevent access to sensitive cloud metadata services
4. Implement proper URL parsing to detect bypasses using URL encoding or alternative representations

Attack Vector

The attack can be performed remotely over the network without requiring authentication. An attacker exploits this vulnerability by sending crafted HTTP requests to the vulnerable API endpoint at app/api/[provider]/[...path]/route.ts.

The attack flow involves manipulating the URL parameter in API requests to point to internal resources. For example, an attacker could target internal services by specifying localhost addresses, access cloud provider metadata endpoints to retrieve sensitive credentials, scan internal network infrastructure by iterating through IP ranges, or access other internal APIs that trust requests from the NextChat server.

The vulnerability mechanism involves the proxy handler function accepting user-supplied URLs and making server-side requests without proper validation. For detailed technical analysis and proof-of-concept information, refer to the GitHub Gist PoC and the GitHub Issue Discussion.

Detection Methods for CVE-2026-7177

Indicators of Compromise

• Unusual outbound requests from the NextChat server to internal IP addresses or cloud metadata endpoints (e.g., 169.254.169.254)
• API requests to the [provider]/[...path] endpoint containing references to internal hostnames, localhost, or private IP ranges
• Unexpected network connections from the application server to services it should not normally communicate with
• Log entries showing requests with URL parameters targeting 127.0.0.1, 10.x.x.x, 172.16.x.x, or 192.168.x.x ranges

Detection Strategies

• Implement network-level monitoring to detect outbound requests from the NextChat server to internal IP ranges or metadata endpoints
• Configure Web Application Firewall (WAF) rules to detect and block SSRF-pattern requests containing internal addresses in URL parameters
• Enable detailed logging for the API endpoints and monitor for suspicious URL patterns in request parameters
• Deploy network segmentation monitoring to alert on unexpected cross-zone traffic from the application tier

Monitoring Recommendations

• Set up alerts for any HTTP requests from the NextChat server to RFC 1918 private address spaces
• Monitor DNS queries from the application server for resolution of internal hostnames or localhost variations
• Implement egress filtering and log all outbound connections from the NextChat application
• Regularly review application logs for requests to the affected API endpoint with anomalous URL parameters

How to Mitigate CVE-2026-7177

Immediate Actions Required

• Upgrade NextChat to a version newer than 2.16.1 when a patch becomes available from the vendor
• Implement network-level egress filtering to prevent the NextChat server from accessing internal networks and cloud metadata endpoints
• Deploy a Web Application Firewall (WAF) with SSRF protection rules in front of the NextChat application
• Review and restrict the network permissions of the server hosting NextChat to limit potential SSRF impact

Patch Information

As of the last update, the ChatGPTNextWeb project has been notified of the vulnerability through a GitHub issue but has not yet released an official patch. Organizations should monitor the NextChat GitHub repository for security updates and apply patches as soon as they become available.

Additional technical details and vulnerability tracking information can be found at VulDB.

Workarounds

• Implement a reverse proxy or API gateway in front of NextChat that validates and restricts outbound URL targets before forwarding requests
• Configure firewall rules to block outbound connections from the NextChat server to internal network segments and cloud metadata IP addresses
• If feasible, disable or restrict access to the vulnerable app/api/[provider]/[...path]/route.ts endpoint until a patch is available
• Deploy network segmentation to isolate the NextChat application from sensitive internal resources

Organizations unable to apply workarounds should consider temporarily taking the NextChat instance offline if it processes sensitive data or has access to critical internal resources.