Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| snykCNA (assigner) | 3.1 | Medium5.6 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C |
| NVDNVD · Modified | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.57% · top 53% of all CVEs (6 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.6.
Weakness
- Prototype Pollution
Affected products
@firebase/util
- affected unspecified – < 0.3.4
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npm@firebase/utilGHSA-fpm5-vv97-jfwg (opens in a new tab)
References (3)
- https://snyk.io/vuln/SNYK-JS-FIREBASEUTIL-1038324 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/firebase/firebase-js-sdk/commit/9cf727fcc3d049551b16ae0698ac33dc2fe45ada (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/firebase/firebase-js-sdk/pull/4001 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-fpm5-vv97-jfwg (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-7765)Record last updated .