Is CVE-2021-40663 actively exploited?

No active exploitation of CVE-2021-40663 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-40663 be exploited remotely?

Yes. CVE-2021-40663 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-40663?

CVE-2021-40663 has a CVSS score of 9.8 (CRITICAL).

HOME VULNERABILITIESCVE-2021-40663

CRITICAL

CVE-2021-40663

CWE-1321Published: June 30, 2022· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official Description

deep.assign npm package 0.0.0-alpha.0 is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution').

NVD Source

Risk Analysis

The deep.assign npm package is vulnerable to prototype pollution, which can lead to critical security impacts. The 9.8 CVSS score reflects the potential for remote code execution.

No public exploit is known, and it is not in the CISA KEV. The vulnerability is remotely exploitable.

Recommended Action

Update the deep.assign package to a secure version or remove the dependency. Audit the application for prototype pollution vulnerabilities.

Generated by the CTIWATCH analysis pipeline from this CVE's metadata (CVSS, EPSS, KEV status, exploit intelligence). Verify against vendor advisories before acting.

Technical Analysis

CVE-2021-40663 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.