CVE-2018-12121
HighCVSS 7.5Exploitation Probability (EPSS)
Very high risk96th percentile - higher than 96% of all known CVEs
Summary
Node.js versions prior to 6.15.0, 8.14.0, 10.14.0, and 11.3.0 are vulnerable to denial of service with large HTTP headers. By combining many requests with maximum-sized headers (almost 80 KB per connection) and carefully timed completion, the HTTP server can abort due to heap allocation failure. Attack potential is mitigated by a load balancer or proxy layer.
Risk Assessment
An attacker can cause unavailability of the HTTP server, leading to application downtime.
Recommendation
Update Node.js to version 6.15.0, 8.14.0, 10.14.0, 11.3.0 or later.
Other vulnerabilities in Node.js
See all- CVE-2026-21637High
A vulnerability in Node.js TLS error handling allows remote attackers to crash or exhaust resources of a TLS server when `pskCallback` or `ALPNCallback` are in use. Synchronous exceptions thrown during these callbacks bypass standard TLS error handling paths, leading to immediate process termination or silent file descriptor leaks that eventually cause denial of service.
- CVE-2025-59466High
A bug has been identified in Node.js error handling where 'Maximum call stack size exceeded' errors become uncatchable when `async_hooks.createHook()` is enabled. Instead of reaching `process.on('uncaughtException')`, the process terminates, making the crash unrecoverable. Applications relying on `AsyncLocalStorage` (v22, v20) or `async_hooks.createHook()` (v24, v22, v20) become vulnerable to denial-of-service crashes triggered by deep recursion under specific conditions.
- CVE-2025-59464High
A memory leak in Node.js's OpenSSL integration occurs when converting X.509 certificate fields to UTF-8 without freeing the allocated buffer. Applications calling socket.getPeerCertificate(true) leak memory per certificate field, allowing remote clients to trigger steady memory growth through repeated TLS connections.
- CVE-2025-23166High
The C++ method SignTraits::DeriveBits() may incorrectly call ThrowException() based on user-supplied inputs when executing in a background thread, crashing the Node.js process. Such cryptographic operations are commonly applied to untrusted inputs, potentially allowing an adversary to remotely crash a Node.js runtime.
- CVE-2025-23085Medium
A memory leak occurs in Node.js when a remote peer abruptly closes the socket without sending a GOAWAY notification, or when nghttp2 detects an invalid header and terminates the connection. This can lead to increased memory consumption and potential denial of service.
- CVE-2024-22018Low
A vulnerability has been identified in Node.js, affecting users of the experimental permission model when the --allow-fs-read flag is used. This flaw arises from an inadequate permission model that fails to restrict file stats through the fs.lstat API, allowing malicious actors to retrieve stats from files they do not have explicit read access to. This vulnerability affects all users using the experimental permission model in Node.js 20 and Node.js 21.
- CVE-2024-22020Medium
A flaw in Node.js allows bypassing network import restrictions by embedding non-network imports in data URLs. This enables an attacker to execute arbitrary code and compromise system security.
- CVE-2024-27982Medium
A critical vulnerability was identified in the HTTP server of the most recent Node version, where malformed headers can lead to HTTP request smuggling. Specifically, placing a space before a content-length header causes it to be misinterpreted, enabling attackers to smuggle a second request within the body of the first.
- CVE-2024-27983High
An attacker can make a Node.js HTTP/2 server completely unavailable by sending a small number of HTTP/2 frame packets. Data can remain in nghttp2 memory after a reset when headers with an HTTP/2 CONTINUATION frame are sent and the client abruptly closes the TCP connection, triggering a race condition.
- CVE-2015-7384High
Node.js versions 4.0.0, 4.1.0, and 4.1.1 allow remote attackers to cause a denial of service.
Original NVD description (English source)
Node.js: All versions prior to Node.js 6.15.0, 8.14.0, 10.14.0 and 11.3.0: Denial of Service with large HTTP headers: By using a combination of many requests with maximum sized headers (almost 80 KB per connection), and carefully timed completion of the headers, it is possible to cause the HTTP server to abort from heap allocation failure. Attack potential is mitigated by the use of a load balancer or other proxy layer.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

