CVE-2020-7765: Google Firebase/util

Medium severity, CVSS 5.3. EPSS: 0.6% chance of exploitation in the next 30 days.

This affects the package @firebase/util before 0.3.4. This vulnerability relates to the deepExtend function within the DeepCopy.ts file. Depending on if user input is provided, an attacker can overwrite and pollute the object prototype of a program.

Affected products

• Google Firebase/util: before 0.3.4 (fixed in 0.3.4)

Published 2020-11-16. Last modified 2026-06-17.