CVE-2026-86083 PUBLISHED

n8n: Expression Sandbox Escape via Shared Builtin Tampering and Code-Printer Injection Leads to Code Execution

Assigner: GitHub_M
Reserved: 04.09.2026 Published: 08.09.2026 Updated: 08.09.2026

n8n is an open source workflow automation platform. Prior to 1.123.76, 2.37.7, and 2.38.2, the legacy expression engine generated source text by calling the mutable global JSON.stringify while printing synthetic string literals and interpolating timezone data. An expression could replace JSON.stringify and cause later generated source to contain executable attacker-controlled code. The affected code-generation paths include packages/@n8n/expression-runtime/src/bridge/isolated-vm-bridge.ts and packages/@n8n/tournament/src/ExpressionBuilder.ts, and the issue does not affect the vm expression engine. This issue is fixed in versions 1.123.76, 2.37.7 and 2.38.2.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 7.7

Product Status

Vendor n8n-io
Product n8n
Versions
  • Version >= 2.38.0, < 2.38.2 is affected
  • Version >= 2.0.0, < 2.37.7 is affected
  • Version < 1.123.76 is affected

References

Problem Types

  • CWE-94: Improper Control of Generation of Code ('Code Injection') CWE