NPM · JULY 2026 · EARLY WARNING

Quasar npm Package <=2.20.1 Vulnerable to Prototype Pollution

EARLY WARNING · UNCONFIRMED. This page describes a developing threat that 0Day surfaced from early signals and has not yet independently confirmed. Details may change. Always verify against the primary sources before acting.
GHSA-3R53-75J5-3G7JSeverity: HIGH

The quasar npm package version 2.20.1 is under investigation for a prototype pollution vulnerability in its extend() utility, which may allow attacker-controlled properties to be written to Object.prototype.

What happened

An early warning has been issued regarding a potential vulnerability in the quasar npm package version 2.20.1. The issue, tracked as GHSA-3R53-75J5-3G7J, involves prototype pollution in the extend() utility. This vulnerability appears to allow an attacker to write properties to Object.prototype, which could lead to unexpected behavior in applications that depend on the quasar package.

Professional software engineers using quasar in their projects should assess their exposure to this vulnerability. If your project depends on quasar version 2.20.1 or earlier, it is recommended to upgrade to a version that addresses this issue or apply a patch if one becomes available. For the latest information and to confirm the vulnerability, consult the primary source at https://github.com/quasarframework/quasar/security/advisories/GHSA-3r53-75j5-3g7j.

As this is an early warning, the full impact and details of the vulnerability are still under investigation. It is crucial to stay updated with the latest advisories and security patches to mitigate any potential risks associated with this vulnerability.

How 0Day mitigates this

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