n8n-io n8n up to 1.123.75/2.37.6/2.38.1 Legacy Expression Engine isolated-vm-bridge.ts JSON.stringify code injection

Summaryinfo

A vulnerability was found in n8n-io n8n up to 1.123.75/2.37.6/2.38.1. It has been rated as critical. The affected element is the function JSON.stringify of the file @n8n/expression-runtime/src/bridge/isolated-vm-bridge.ts of the component Legacy Expression Engine. Performing a manipulation results in code injection. This vulnerability is cataloged as CVE-2026-86083. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in n8n-io n8n up to 1.123.75/2.37.6/2.38.1. It has been classified as critical. This affects the function JSON.stringify of the file @n8n/expression-runtime/src/bridge/isolated-vm-bridge.ts of the component Legacy Expression Engine. The manipulation with an unknown input leads to a code injection vulnerability. CWE is classifying the issue as CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-86083 since 09/04/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

Upgrading to version 1.123.76, 2.37.7 or 2.38.2 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• n8n-io

Name

• n8n

Version

• 1.123.0
• 1.123.1
• 1.123.2
• 1.123.3
• 1.123.4
• 1.123.5
• 1.123.6
• 1.123.7
• 1.123.8
• 1.123.9
• 1.123.10
• 1.123.11
• 1.123.12
• 1.123.13
• 1.123.14
• 1.123.15
• 1.123.16
• 1.123.17
• 1.123.18
• 1.123.19
• 1.123.20
• 1.123.21
• 1.123.22
• 1.123.23
• 1.123.24
• 1.123.25
• 1.123.26
• 1.123.27
• 1.123.28
• 1.123.29
• 1.123.30
• 1.123.31
• 1.123.32
• 1.123.33
• 1.123.34
• 1.123.35
• 1.123.36
• 1.123.37
• 1.123.38
• 1.123.39
• 1.123.40
• 1.123.41
• 1.123.42
• 1.123.43
• 1.123.44
• 1.123.45
• 1.123.46
• 1.123.47
• 1.123.48
• 1.123.49
• 1.123.50
• 1.123.51
• 1.123.52
• 1.123.53
• 1.123.54
• 1.123.55
• 1.123.56
• 1.123.57
• 1.123.58
• 1.123.59
• 1.123.60
• 1.123.61
• 1.123.62
• 1.123.63
• 1.123.64
• 1.123.65
• 1.123.66
• 1.123.67
• 1.123.68
• 1.123.69
• 1.123.70
• 1.123.71
• 1.123.72
• 1.123.73
• 1.123.74
• 1.123.75
• 2.37.0
• 2.37.1
• 2.37.2
• 2.37.3
• 2.37.4
• 2.37.5
• 2.37.6
• 2.38.0
• 2.38.1

Website

• Product: https://github.com/n8n-io/n8n/

CPE 2.3info

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CPE 2.2info

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