CVE-2021-26707: Merge-Deep Project Merge-Deep

Critical severity, CVSS 9.8. EPSS: 1.9% chance of exploitation in the next 30 days.

The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.

Affected products

• Merge-Deep Project Merge-Deep: before 3.0.3 (fixed in 3.0.3)
• Netapp E-Series Performance Analyzer: affected versions not specified

Published 2021-06-02. Last modified 2026-06-17.