Prototype Pollution in realms-shim

CRITICAL 10.0CVE-2021-23594 · GHSA-pwm7-qr6j-3vjg · Published 10/01/2022 · updated 17/06/2026

In short

CVE-2021-23594 is a CRITICAL (CVSS 10.0) vulnerability affecting realms-shim.
Chance of exploitation in the next 30 days (EPSS): 1.8%, higher than 78.8% of all vulnerabilities.
No patched version is listed yet: follow the vendor's advisory in References.

Package	Affected versions	Patched versions
realms-shim npm	`≤ 1.2.2`	No fix yet

All versions of package realms-shim are vulnerable to Sandbox Bypass via a Prototype Pollution attack vector.

NVD description

All versions of package realms-shim are vulnerable to Sandbox Bypass via a Prototype Pollution attack vector.

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