exceljs through 4.4.0 fails to neutralize leading equals, plus, minus, or at signs in cell values written to CSV output.

Code

The project this record applies to. Exploit listings stay in References.

• Repository · github.com
• Repository · github.com

Timeline

Detection, updates, and resolution for this record.

1. Aug 24, 2026 · NIST NVD

   Detected

   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.

2. Oct 14, 2026 · NIST NVD

   Updated

   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.

Sources

• CVE.orgVulnerability recordCVE-2026-78209

  Official CVE identifier

  cve.org
• FIRST EPSSExploitation probabilityCVE-2026-78209

  30-day exploitation probability 0.4%

  first.org
• NIST NVDVulnerability recordCVE-2026-78209

  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 exfiltr

  nvd.nist.gov

References

• Reference · github.com
• Reference · github.com
• Reference · github.com
• Reference · vulncheck.com