Next.js is a React framework for building full-stack web applications. Starting in version 13.0.0 and prior to versions 13.5.8, 14.2.21, and 15.1.2, Next.js is vulnerable to a Denial of Service (DoS) attack that allows attackers to construct requests that leaves requests to Server Actions hanging until the hosting provider cancels the function execution. This vulnerability can also be used as a Denial of Wallet (DoW) attack when deployed in providers billing by response times. (Note: Next.js server is idle during that time and only keeps the connection open. CPU and memory footprint are low during that time.). Deployments without any protection against long running Server Action invocations are especially vulnerable. Hosting providers like Vercel or Netlify set a default maximum duration on function execution to reduce the risk of excessive billing. This is the same issue as if the incoming HTTP request has an invalid `Content-Length` header or never closes. If the host has no other mitigations to those then this vulnerability is novel. This vulnerability affects only Next.js deployments using Server Actions. The issue was resolved in Next.js 13.5.8, 14.2.21, and 15.1.2. We recommend that users upgrade to a safe version. There are no official workarounds.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 5.3, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts and limited availability for affected systems. Impacting 1 product from vercel organizations running these solutions should prioritize assessment and patching.
Reported in 2025, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2025-01-03T21:15:13.550
2025-09-10T15:48:41.830
Analyzed
CVSSv3.1: 5.3 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | vercel | next.js | < 13.5.8 | Yes |
| Application | vercel | next.js | < 14.2.21 | Yes |
| Application | vercel | next.js | < 15.1.2 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For vercel's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.