NPM · JULY 2026 · EARLY WARNING

Quasar npm Package <=2.20.1: Prototype Pollution Vulnerability

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 reportedly vulnerable to prototype pollution through its extend() utility. This can allow attacker-controlled properties to be written to Object.prototype.

What happened

An early warning has been issued regarding a potential prototype pollution vulnerability in the quasar npm package version 2.20.1. The vulnerability appears to be present in the extend() utility, which can allow attacker-controlled properties to be written to Object.prototype. This issue is currently under investigation by the maintainers of the quasar package. To assess your exposure, check if your project is using quasar version 2.20.1 or earlier. If so, consider upgrading to a version that includes a fix for this vulnerability, or avoid using the extend() utility with untrusted input. For the latest information, consult the primary source at https://github.com/quasarframework/quasar/security/advisories/GHSA-3r53-75j5-3g7j.

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