CVE-2021-25945

CRITICALNVD 9.89.8—

9.8

Prototype pollution vulnerability in 'js-extend' versions 0.0.1 through 1.0.1 allows attacker to cause a denial of service and may lead to remote code execution.

CVSS v3: 9.8
EG Score: 9.8(medium)
EPSS: 85.7%
KEV: Not listed

Published

May 26, 2021

Last Modified

November 21, 2024

References (2)

vulnerabilitylab@mendhttps://www.whitesourcesoftware.com/vulnerability-database/CVE-2021-25945
af854a3a-2127-422b-91ae-364da2661108https://www.whitesourcesoftware.com/vulnerability-database/CVE-2021-25945

Patch Availability(1)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
npm	js-extend	—	ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)

npm(1)

Package	Vulnerable range	Fixed in	Dependents
js-extend	—	—	—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 7× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-05-27 13:39 UTCepss_batch
2026-05-27 13:39 UTCepss_batch
2026-05-26 16:07 UTCEG score recompute
2026-05-26 16:06 UTCGHSA enrichment
2026-05-26 13:42 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch

Frequently asked(5)

What is CVE-2021-25945?

CVE-2021-25945 is a critical vulnerability published on May 26, 2021. Prototype pollution vulnerability in 'js-extend' versions 0.0.1 through 1.0.1 allows attacker to cause a denial of service and may lead to remote code execution.

When was CVE-2021-25945 disclosed?

CVE-2021-25945 was first published in the National Vulnerability Database on May 26, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-25945 actively exploited?

CVE-2021-25945 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 85.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-25945?

CVE-2021-25945 has a CVSS v3 base score of 9.8 (NVD).

How do I remediate CVE-2021-25945?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-25945, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-25945

Explore →

Is Your Infrastructure Affected by CVE-2021-25945?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs