How severe is CVE-2020-7765?

CVE-2020-7765 has a CVSS score of 5.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2020-7765?

CVE-2020-7765 affects the following packages: @firebase/util (npm). Ecosystems affected: npm.

How do I fix CVE-2020-7765?

Update @firebase/util to 0.3.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-7765 is resolved across your whole dependency graph.

How do I detect CVE-2020-7765 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @firebase/util. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2020-7765 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2020-7765?

O3 pinpoints whether CVE-2020-7765 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2020-7765 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2020-7765, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

When was CVE-2020-7765 published, and has it been updated?

CVE-2020-7765 was published on November 16, 2020 and was last updated on July 9, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦

📦 npm

Not in CISA KEV

MEDIUM severity

CVE-2020-7765

MEDIUMFix: firebase/firebase-js-sdk@9cf727f

CVE-2020-7765 is a medium-severity (CVSS 5.3) vulnerability in @firebase/util. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2020-7765 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Uncontrolled Resource Consumption in firebase

Also known asGHSA-fpm5-vv97-jfwg

Published

Nov 16, 2020

Updated

Jul 9, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

1 known

Exploitation data as of Jul 9, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Real-World Exposure

1 pkg affected

📦@firebase/util

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.

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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@firebase/util`	all versions	0.3.4

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

This affects the package @firebase/util before 0.3.4. This vulnerability…

snyk.ioNVDDec 2020

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @firebase/util. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update @firebase/util to 0.3.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-7765 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2020-7765 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2020-7765. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2020-7765 in your dependencies?

O3 detects CVE-2020-7765 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works