Prototype Pollution

Overview exceljs is a package to Read, manipulate and write spreadsheet data and styles to XLSX and JSON. Affected versions of this package are vulnerable to Prototype Pollution through Note.model serialization in lib/utils/under-dash.js. An attacker can modify Object.prototype and influence late...

External Control of File Name or Path

Overview exceljs is a package to Read, manipulate and write spreadsheet data and styles to XLSX and JSON. Affected versions of this package are vulnerable to External Control of File Name or Path via Workbook.addImagefilename in lib/xlsx/xlsx.js addMedia. An attacker can read arbitrary files...

CSV Injection

Overview exceljs is a package to Read, manipulate and write spreadsheet data and styles to XLSX and JSON. Affected versions of this package are vulnerable to CSV Injection through the CSV.write process in lib/csv/csv.js. An attacker can trigger spreadsheet formula execution by supplying a cell...

Improper Handling of Highly Compressed Data (Data Amplification)

Overview exceljs is a package to Read, manipulate and write spreadsheet data and styles to XLSX and JSON. Affected versions of this package are vulnerable to Improper Handling of Highly Compressed Data Data Amplification via Workbook.xlsx.load in lib/xlsx/xlsx.js. An attacker can exhaust memory a...

CVE-2026-78209

exceljs-hardened versions before 5.0.0 fail to neutralize leading equals, plus, minus, or at signs in cell values written to CSV output. Attackers who can influence exported cell values can inject formulas that execute when the CSV file is opened in a spreadsheet application, potentially...

CVE-2026-78208

exceljs-hardened before 5.0.0 contains a path traversal vulnerability in the Workbook.addImage function that fails to validate file paths. Attackers can supply arbitrary file paths to read any file accessible to the Node.js process and embed it in the generated workbook...

CVE-2026-78207

exceljs-hardened before 5.0.0 contains a prototype pollution vulnerability in the deepMerge helper that fails to reject proto, constructor, or prototype keys when merging note objects. Attackers can assign parsed JSON with a malicious proto property to cell notes, modifying Object.prototype and...

CVE-2026-78206

exceljs-hardened before 5.0.0 decompresses all entries from supplied xlsx archives into memory without limits on entry size, total size, or compression ratio. Attackers can upload highly compressed workbooks that expand to gigabytes in memory, exhausting available resources and causing denial of...

CVE-2026-78209 exceljs through 4.4.0 CSV Formula Injection via Unescaped Cell Values

exceljs-hardened versions before 5.0.0 fail to neutralize leading equals, plus, minus, or at signs in cell values written to CSV output. Attackers who can influence exported cell values can inject formulas that execute when the CSV file is opened in a spreadsheet application, potentially...

CVE-2026-78209

exceljs-hardened versions before 5.0.0 are vulnerable to CSV formula injection . The library fails to neutralize leading equals, plus, minus, or at signs in cell values written to CSV output. An attacker who can influence exported cell values can inject spreadsheet formulas that execute when the ...

EUVD-2026-64684

exceljs-hardened versions before 5.0.0 fail to neutralize leading equals, plus, minus, or at signs in cell values written to CSV output. Attackers who can influence exported cell values can inject formulas that execute when the CSV file is opened in a spreadsheet application, potentially...

CVE-2026-78209 exceljs through 4.4.0 CSV Formula Injection via Unescaped Cell Values

exceljs-hardened versions before 5.0.0 fail to neutralize leading equals, plus, minus, or at signs in cell values written to CSV output. Attackers who can influence exported cell values can inject formulas that execute when the CSV file is opened in a spreadsheet application, potentially...

CVE-2026-78207

exceljs-hardened before 5.0.0 (also tracked as exceljs through 4.4.0) contains a prototype pollution vulnerability in the deepMerge helper. The helper fails to reject __proto__, constructor, or prototype keys when merging note objects, allowing an attacker to assign parsed JSON with a malicious _...

CVE-2026-78208

exceljs-hardened before 5.0.0 (and exceljs through 4.4.0) is affected by a path traversal vulnerability in the Workbook.addImage() function. The function fails to validate file path inputs, allowing an attacker to supply an arbitrary path that reads any file accessible to the Node.js process and ...

EUVD-2026-64682

exceljs-hardened before 5.0.0 contains a prototype pollution vulnerability in the deepMerge helper that fails to reject proto, constructor, or prototype keys when merging note objects. Attackers can assign parsed JSON with a malicious proto property to cell notes, modifying Object.prototype and...

CVE-2026-78207 exceljs through 4.4.0 Prototype Pollution via deepMerge Reached From Note Serialization

exceljs-hardened before 5.0.0 contains a prototype pollution vulnerability in the deepMerge helper that fails to reject proto, constructor, or prototype keys when merging note objects. Attackers can assign parsed JSON with a malicious proto property to cell notes, modifying Object.prototype and...

CVE-2026-78208 exceljs through 4.4.0 Path Traversal via Unvalidated addImage filename

exceljs-hardened before 5.0.0 contains a path traversal vulnerability in the Workbook.addImage function that fails to validate file paths. Attackers can supply arbitrary file paths to read any file accessible to the Node.js process and embed it in the generated workbook...

CVE-2026-78207 exceljs through 4.4.0 Prototype Pollution via deepMerge Reached From Note Serialization

exceljs-hardened before 5.0.0 contains a prototype pollution vulnerability in the deepMerge helper that fails to reject proto, constructor, or prototype keys when merging note objects. Attackers can assign parsed JSON with a malicious proto property to cell notes, modifying Object.prototype and...

EUVD-2026-64683

exceljs-hardened before 5.0.0 contains a path traversal vulnerability in the Workbook.addImage function that fails to validate file paths. Attackers can supply arbitrary file paths to read any file accessible to the Node.js process and embed it in the generated workbook...

CVE-2026-78208 exceljs through 4.4.0 Path Traversal via Unvalidated addImage filename

exceljs-hardened before 5.0.0 contains a path traversal vulnerability in the Workbook.addImage function that fails to validate file paths. Attackers can supply arbitrary file paths to read any file accessible to the Node.js process and embed it in the generated workbook...