CVE-2025-57822 Scanner

Next.js is a popular open-source React framework deployed by developers globally for building server-side rendered or statically exported applications. It is maintained by Vercel and is used for building high-performance, fast-loading websites and applications. Companies use Next.js for projects that benefit from server-side rendering, API integration, and building static sites with dynamic capabilities. Due to its integration with modern JavaScript tooling and its ease of use, it has become widely adopted in both small projects and large enterprise environments. Next.js also supports various backend and frontend server-side operations, making it a versatile tool for web developers. Security vulnerabilities in such a popular framework can have widespread implications, affecting frontend and backend operations.

Server-Side Request Forgery (SSRF) is a web security vulnerability that allows an attacker to manipulate a server to make HTTP requests to any arbitrary domain. SSRF vulnerabilities can cause a server to connect to internal resources, carrying out operations typically restricted to trusted sources. In this instance, the vulnerability in Next.js versions prior to 14.2.32 and 15.4.7 arises from insecure handling of request headers, particularly when these headers are passed to the NextResponse.next() function. Exploiting this can potentially lead to sensitive data disclosure or manipulation of underlying server functionality. As a consequence, unauthorized external requests might be made, facilitating further attack strategies such as reconnaissance or data exfiltration.

The technical aspect of this SSRF vulnerability revolves around how Next.js processes request headers. The affected versions erroneously allow attackers to influence server requests by injecting headers that are used without sufficient validation. In this scenario, the issue occurs when headers are forwarded without sanitizing destination URLs, acting as a vector for SSRF. Attackers might deploy a crafted payload that leverages these headers to direct unwanted requests towards an internal network or third-party services. Through manipulating the 'X-Middleware-Rewrite' or 'Location' headers, a bad actor can direct traffic to an attacker-controlled server. This rebellion against intended routing might remain unnoticed unless stringent monitoring of outgoing requests is maintained.

If successfully exploited, SSRF vulnerabilities can have serious consequences. Attackers may gain unauthorized access to internal server data or services, potentially leading to data leaks or further exploitation of the server environment. They could execute discriminatory information operations, avoid access control safeguards, and bypass internal firewalls. Additionally, such vulnerabilities can enable attackers to interact with third-party systems using the compromised server as a proxy, masking the true origin of their requests. This could ultimately result in severe reputational damage to the service and potential legal or financial repercussions due to data protection laws and regulations.

REFERENCES

• https://github.com/vercel/next.js/security/advisories/GHSA-4342-x723-ch2f
• https://vercel.com/changelog/cve-2025-57822
• https://nvd.nist.gov/vuln/detail/CVE-2025-57822