Skip to main content
Live Webinar with SANS (June 25)— Agentic CTI Automation for Fun & ProfitRegister Free
Mallory
Medium

Node.js Permission Model UDS permission check bypass

IdentifiersCVE-2026-21711CWE-863

CVE-2026-21711 is a medium-severity authorization bypass in the Node.js Permission Model affecting Node.js 25.x. When the experimental Permission Model is enabled with --permission and network access is intentionally not granted via --allow-net, Node.js correctly enforces permission checks for comparable network operations but fails to enforce them for Unix Domain Socket (UDS) server bind/listen operations. As a result, code running in a supposedly network-restricted process can still create and expose local IPC endpoints over UDS, bypassing the intended network restriction boundary and enabling unauthorized local inter-process communication with other processes on the same host.

Share:
For your environment

Are you exposed to this one?

Mallory correlates every CVE against your assets, your vendors, and active adversary campaigns. Know which vulnerabilities matter for you, not just which ones are loud.

ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows code executing inside a restricted Node.js process to bypass the intended network isolation imposed by the Permission Model and establish Unix Domain Socket server endpoints despite the absence of --allow-net. This undermines the security guarantees of the permission boundary, enabling unauthorized local IPC with other host processes. Depending on the application design and local environment, this may permit data exchange with trusted local services, policy bypass, and expansion of the attack surface beyond what operators intended when disabling network access.

Mitigation

If you can’t patch tonight, do this now.

Until patched, avoid relying on the experimental Node.js Permission Model alone to prevent local IPC via Unix Domain Sockets in 25.x. Do not execute untrusted code in processes where --permission is enabled but --allow-net is omitted if local socket creation would be security-relevant. Apply OS-level isolation controls as compensating measures, such as filesystem and runtime sandboxing that restrict socket path creation and inter-process communication, and minimize exposure to local services reachable over UDS.

Remediation

Patch, then assume compromise.

Upgrade Node.js to a patched release that includes the fix for CVE-2026-21711. The provided context identifies Node.js v25.8.2 as the patched 25.x release. If running affected 25.x builds with the experimental Permission Model, move to the fixed version as soon as possible.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
NodejsNodejsapplication
Rocky LinuxNodejs24application
Rocky LinuxRocky Linuxoperating_system

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

What this page doesn’t show

The version that knows your environment.

This page is what’s public. Mallory adds the parts that aren’t: which of your assets are affected, which adversaries are exploiting it right now, which detections to deploy, and what to do tonight.
Exposure mapping

Query your assets running an affected version, and investigate the blast radius.

Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity2

Community discussion across Reddit, Mastodon, and other social sources.