How severe is CVE-2020-8147?

No CVSS score has been assigned to CVE-2020-8147 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2020-8147?

CVE-2020-8147 affects the following packages: utils-extend (npm). Ecosystems affected: npm.

How do I fix CVE-2020-8147?

No patched version of utils-extend has shipped for CVE-2020-8147 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.

How do I detect CVE-2020-8147 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for utils-extend, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2020-8147 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.

Is CVE-2020-8147 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2020-8147, 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.

What is the EPSS score for CVE-2020-8147?

CVE-2020-8147 has an EPSS (Exploit Prediction Scoring System) score of 3.1%, placing it in the 88th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2020-8147?

CVE-2020-8147 is classified as CWE-471 (CWE-471), Improper Input Validation (CWE-20). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2020-8147 published, and has it been updated?

CVE-2020-8147 was published on September 3, 2020 and was last updated on November 8, 2023. 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

CVE-2020-8147 — utils-extend

CVE-2020-8147 is a CWE-471 vulnerability in utils-extend. 1 public exploit reference exists, so weaponization risk is real. No vendor fix is recorded yet; mitigation options are listed below.

Prototype Pollution

Published

Sep 3, 2020

Updated

Nov 8, 2023

Affected

1 pkg

Patched

See advisory

Exploits

1 known

Exploitation data as of Oct 8, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

3.1%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs88th percentile — riskier than 88% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

14other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

utils-extendnpm

53Kdownloads / week

Description

All versions of utils-extend are vulnerable to prototype pollution. The extend function does not restrict the modification of an Object's prototype, which may allow an attacker to add or modify an existing property that will exist on all objects.

Recommendation

No fix is currently available. Consider using an alternative package until a fix is made available.

Affected Packages

1 total

Ecosystem	Package	Vulnerable range	Fix
📦npm	`utils-extend`	≥ 0.0.0	No fix

Affected Products

1 product · 1 configurations

Application

utils-extendutils-extend_project

≤ 1.0.8

range

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.

Flaw in input validation in npm package utils-extend version 1.0.8 and e…

hackerone.comNVDApr 2020

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for utils-extend, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of utils-extend has shipped for CVE-2020-8147 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
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.

Frequently Asked Questions

All versions of `utils-extend` are vulnerable to prototype pollution. The `extend` function does not restrict the modification of an Object's prototype, which may allow an attacker to add or modify an existing property that will exist on all objects. ## Recommendation No fix is currently available. Consider using an alternative package until a fix is made available.

O3 Security · Impact-Aware SCA

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