n8n before 1.123.69 Remote Code Execution via EventEmitter Prototype Pollution (CVE-2026-77077) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-77077

n8n before 1.123.69 Remote Code Execution via EventEmitter Prototype Pollution

Answer in brief

CVE-2026-77077 records a Unknown severity vulnerability in n8n before 1.123.69 Remote Code Execution via EventEmitter Prototype Pollution. The current sources do not mark it as known exploited. The current feed maps n8n-io/n8n (generic), n8n-io/n8n (generic), n8n-io/n8n (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 20, 2026Updated Aug 20, 2026Source checked Aug 20, 2026First seen by HOL Aug 20, 2026Material review Aug 20, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 3 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps n8n-io/n8n (generic), n8n-io/n8n (generic), n8n-io/n8n (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
n8n-io/n8ngeneric	>=0 <1.123.69	1.123.69
n8n-io/n8ngeneric	>=0 <2.34.1	2.34.1
n8n-io/n8ngeneric	>=0 <2.33.4	2.33.4

Recommended response

Check inventory. Check lockfiles and deployed manifests for n8n-io/n8n, n8n-io/n8n, n8n-io/n8n.
Review the reported fix. Update n8n-io/n8n to 1.123.69; n8n-io/n8n to 2.34.1; n8n-io/n8n to 2.33.4 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 20, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 20, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 20, 2026

Sources and claim methodology

Upstream source description

n8n versions before 1.123.69, 2.33.4, and 2.34.1 contain a JavaScript task runner VM sandbox escape. The runner's prototype-freezing routine covers globalThis functions but not internal module constructors such as EventEmitter, allowing an authenticated user with Code node access to exploit prototype pollution to execute arbitrary commands within the runner container. Because the polluted prototype is a process-wide object, the corruption persists across other tenants' Code node executions on the same shared runner. On v1.x instances without task runners enabled, Code node JavaScript runs directly in the main n8n process, where the impact could be higher.

Quoted source text, attributed separately from HOL analysis.