Dangerous column header "${header.trim()}" found in ${format

Error message

Dangerous column header "${header.trim()}" found in ${format} data

What it means

Error "Dangerous column header "${header.trim()}" found in ${format} data" thrown in n8n-io/n8n.

Source

Thrown at packages/@n8n/instance-ai/src/parsers/structured-file-parser.ts:306

		return { rawHeaders: [], allRows: [] };
	}

	let rawHeaders: string[];
	let dataRows: string[][];

	if (options.hasHeader) {
		rawHeaders = records[0];
		dataRows = records.slice(1);
	} else {
		const colCount = records[0].length;
		rawHeaders = Array.from({ length: colCount }, (_, i) => `column_${i}`);
		dataRows = records;
	}

	// Check for dangerous keys in CSV/TSV headers (consistent with JSON validation)
	for (const header of rawHeaders) {
		if (DANGEROUS_KEYS.has(header.trim())) {
			throw new Error(`Dangerous column header "${header.trim()}" found in ${format} data`);
		}
	}

	return { rawHeaders, allRows: dataRows };
}

function parseJson(content: string): {
	rawHeaders: string[];
	allRows: Array<Record<string, unknown>>;
} {
	let parsed: unknown;
	try {
		parsed = JSON.parse(content);
	} catch {
		throw new Error('Invalid JSON: failed to parse');
	}

	if (!Array.isArray(parsed)) {

View on GitHub (pinned to 5ac6606e81)

When it happens

Trigger: Thrown at packages/@n8n/instance-ai/src/parsers/structured-file-parser.ts:306 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of n8n-io/n8n@5ac6606e81 (2026-08-12). Data as JSON: /api/errors/118cb8ca918ef2f1. Report an issue: GitHub.