CVE-2026-46625

HIGH(7.5)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Risk Signal Score19/100 — NIEDRIG

CVSS 7.5 — Hoch

EPSS-Score

Exploit-Wahrscheinlichkeit (30 Tage)

CVSS Score

7.5

Technische Schwere

Beschreibung

JavaScript Cookie is a JavaScript API for handling cookies, client-side. Prior to version 3.0.7, js-cookie's internal assign() helper copies properties with for...in + plain assignment. When the source object is produced by JSON.parse, the JSON object's "__proto__" member is an own enumerable property, so the for…in enumerates it and the target[key] = source[key] write triggers the Object.prototype.__proto__ setter on the fresh target ({}). The result is a per-instance prototype hijack: Object.prototype itself is untouched, but the merged attributes object now inherits attacker-controlled keys. Because the consuming set() function then enumerates the merged object with another for...in, every key the attacker placed on the polluted prototype lands in the resulting Set-Cookie string as an attribute pair. The attacker can set domain=, secure=, samesite=, expires=, and path= on cookies whose attributes the developer thought were locked down. This issue has been patched in version 3.0.7.

GitHub Advisories

GHSA-qjx8-664m-686jHIGH

JavaScript Cookie: Per-instance prototype hijack in assign() enables cookie-attribute injection

npm/js-cookie→ 3.0.7

GitHub Advisory

CVE-2026-46625

Beschreibung

GitHub Advisories

Referenzen