GHSA-6xcw-7xm6-48c6: n8n: Expression Sandbox Escape via Shared Builtin Tampering and Code-Printer Injection Leads to Code Execution

Summary

Two code-generation stages in n8n's legacy expression engine called the global JSON.stringify at generation time. An expression that replaced that global could change the source that was generated and then executed, turning literal data into executable code. The vm expression engine, the default on patched releases, is not affected.

Mitigation

Fixed in n8n 1.123.76, 2.37.7, and 2.38.2. If upgrading is not immediately possible, set N8N_EXPRESSION_ENGINE=vm, restrict instance access to fully trusted users, and run the n8n process under a dedicated low-privilege OS user account. These workarounds do not fully remediate the risk and are short-term measures only.

Affected packages in the Exposure Registry

Matched by package name and ecosystem. Each entry shows whether the package delegates to a language model and how many tracked packages depend on it.

• n8nnpmDeclares an LLM dependency

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