CVE-2020-7765 json
Prototype Pollution
published 2020-11-16 5 y ago modified 2026-09-10 1 mo ago also GHSA-fpm5-vv97-jfwg , EUVD-2021-1064
- cvss
- 5.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 47%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm @firebase/util 0.3.4
- n/a @firebase/util 0.3.4
- github.com/firebase/firebase-js-sdk@9cf727f commit
- github.com/firebase/firebase-js-sdk#4001 pull request
Exploit prediction
0.57% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- snyk.io https://snyk.io/vuln/SNYK-JS-FIREBASEUTIL-1038324 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.6 | 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 |
| CNA | 3.1 | 5.6 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L |
| NVD | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:P/A:N |
| GitHub | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @firebase/util | <0.3.4 |
0.3.4 |
Affected products
- n/a @firebase/util
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
github.com
/firebase/firebase-js-sdk/commit/9cf727fcc3d049551b16ae0698ac33dc2fe45ada
web, patch, third-party-advisory
-
github.com
/firebase/firebase-js-sdk/pull/4001
web, patch, third-party-advisory
-
snyk.io
/vuln/SNYK-JS-FIREBASEUTIL-1038324
web, exploit, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2020-7765
advisory
Sources
- CVE List CVE-2020-7765
- GitHub Advisory GHSA-fpm5-vv97-jfwg
- NVD CVE-2020-7765
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