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Vulnerability DatabaseCVE-2021-23568

CVE-2021-23568: 
JavaScript vulnerability analysis and mitigation

Overview

The package extend2 before version 1.0.1 was discovered to contain a Prototype Pollution vulnerability via the extend function due to unsafe recursive merge. The vulnerability was assigned CVE-2021-23568 and was disclosed on January 10, 2022 (NVD).

Technical details

The vulnerability exists in the extend function's recursive merge functionality where insufficient input sanitization allows for prototype pollution. The issue received a CVSS v3.1 base score of 9.8 (CRITICAL) from NIST and 7.3 (HIGH) from Snyk, with the attack vector being network-based, requiring no privileges or user interaction (NVD).

Impact

A successful exploitation of this vulnerability could allow an attacker to modify properties within the global prototype chain, potentially leading to denial of service (DoS) at minimum. The vulnerability affects all versions of extend2 package before 1.0.1 (NVD).

Mitigation and workarounds

The vulnerability has been fixed in version 1.0.1 of extend2. The fix involves adding a check to prevent proto property copying, as demonstrated in the patch commit. Users are advised to upgrade to version 1.0.1 or later (GitHub Patch).

Additional resources

Source: This report was generated using AI

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