CVE-2026-48936 in Node.js
Summary
by MITRE • 06/26/2026
A flaw in Node.js Permission API can cause a local server to be started (via a Unix domain socket), even without the `--allow-net` permission.
This vulnerability affects one supported release line: **Node.js 26**.
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Analysis
by VulDB Data Team • 06/26/2026
The vulnerability in Node.js Permission API represents a significant security regression that undermines the core principle of privilege separation within the runtime environment. This flaw specifically impacts Node.js version 26 and allows unauthorized local server initialization through Unix domain sockets without requiring explicit network permissions. The issue stems from an improper validation mechanism within the permission system that fails to adequately enforce access controls for socket operations, creating a potential attack vector where malicious code could bypass intended security boundaries.
The technical implementation of this vulnerability resides in the Node.js Permission API's handling of Unix domain socket operations. When applications attempt to create or bind to Unix domain sockets, the permission system should verify whether appropriate permissions have been granted before allowing such operations to proceed. However, the flaw enables a bypass where network-related operations can be executed through Unix sockets without the required `--allow-net` flag being present. This creates a scenario where local services could be started or accessed without proper authorization, effectively weakening the sandboxing capabilities that Node.js provides.
From an operational perspective, this vulnerability presents a serious risk to systems running Node.js 26 where applications might be executing with restricted permissions. An attacker could potentially leverage this flaw to establish unauthorized communication channels, create backdoors, or expose sensitive services through Unix domain sockets. The implications extend beyond simple privilege escalation as it affects the fundamental security model of Node.js applications that rely on permission-based access controls for network operations.
This vulnerability aligns with CWE-284: Improper Access Control and maps to ATT&CK technique T1068: Exploitation for Privilege Escalation. The weakness demonstrates how inadequate permission validation can lead to unauthorized system access and service exposure. Organizations should consider this issue as part of their broader security posture assessment, particularly in environments where Node.js applications handle sensitive data or operate in multi-tenant configurations.
The recommended mitigation strategy involves upgrading to a patched version of Node.js 26 or applying the relevant security patches immediately. System administrators should also review existing applications for potential exploitation opportunities and consider implementing additional monitoring controls around Unix socket usage. Organizations running affected systems should conduct thorough security assessments to identify any unauthorized services that might have been initiated through this vulnerability, ensuring proper access control mechanisms are enforced across all network operations within their Node.js environments.