CVE-2026-21711
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk4th percentile - higher than 4% of all known CVEs
Summary
A flaw in Node.js Permission Model network enforcement leaves Unix Domain Socket (UDS) server operations without the required permission checks, while all comparable network paths correctly enforce them. As a result, code running under --permission without --allow-net can create and expose local IPC endpoints, allowing communication with other processes on the same host outside of the intended network restriction boundary. This vulnerability affects Node.js 25.x processes using the Permission Model where --allow-net is intentionally omitted to restrict network access. Note that --allow-net is currently an experimental feature.
Risk Assessment
Node.js applications running with network restrictions may be vulnerable to unauthorized local communication, potentially leading to process isolation breaches and data leakage.
Recommendation
Update Node.js to a patched version, or temporarily avoid using the Permission Model without --allow-net if possible.
Other vulnerabilities in Node.js
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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
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- 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.
- CVE-2017-14849High
Node.js 8.5.0 before 8.6.0 allows remote attackers to access unintended files, because a change to '..' handling was incompatible with the pathname validation used by unspecified community modules.
- CVE-2017-11499High
Node.js versions from 4.0 to 4.8.3, all 5.x versions, and versions 6.0 to 6.11.0, 7.0 to 7.10.0, and 8.0 to 8.1.3 were susceptible to hash flooding DoS attacks. This was due to the HashTable seed being constant across a given released version of Node.js.
- CVE-2016-2216High
The HTTP header parsing code in Node.js in versions 0.10.x before 0.10.42, 0.11.6 through 0.11.16, 0.12.x before 0.12.10, 4.x before 4.3.0, and 5.x before 5.6.0 allows remote attackers to bypass an HTTP response-splitting protection mechanism via UTF-8 encoded Unicode characters in the HTTP header.
- CVE-2016-2086High
Node.js versions 0.10.x before 0.10.42, 0.12.x before 0.12.10, 4.x before 4.3.0, and 5.x before 5.6.0 are vulnerable to HTTP request smuggling attacks via a crafted Content-Length HTTP header.
- CVE-2015-8027High
Node.js versions 0.12.x before 0.12.9, 4.x before 4.2.3, and 5.x before 5.1.1 do not ensure the availability of a parser for each HTTP socket, allowing remote attackers to cause a denial of service via a pipelined HTTP request.
- CVE-2026-21710High
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Original NVD description (English source)
A flaw in Node.js Permission Model network enforcement leaves Unix Domain Socket (UDS) server operations without the required permission checks, while all comparable network paths correctly enforce them. As a result, code running under `--permission` without `--allow-net` can create and expose local IPC endpoints, allowing communication with other processes on the same host outside of the intended network restriction boundary. This vulnerability affects Node.js **25.x** processes using the Permission Model where `--allow-net` is intentionally omitted to restrict network access. Note that `--allow-net` is currently an experimental feature.

