CVE-2026-78209highCWE-1236

CVE-2026-78209: high-severity vulnerability in exceljs

exceljs through 4.4.0 CSV Formula Injection via Unescaped Cell Values

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.4epss 0.4%
exceljs through 4.4.0 fails 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 exfiltrating data or performing other malicious actions.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N
Affected products
exceljs · exceljs
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