{"id":"CVE-2026-123567","published":"2026-11-08T02:16:49.360","lastModified":"2026-11-08T02:16:49.360","description":"Sveltejs devalue before 5.6.4 contains a prototype injection vulnerability that allows attackers to inject __proto__ own properties into objects returned by devalue.parse and devalue.unflatten. Attackers can supply crafted serialized input that, when downstream code merges results via Object.assign, alters the target object's prototype.","cvssScore":3.7,"cvssSeverity":"LOW","cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","cwes":["CWE-1321"],"vendors":[],"products":[],"references":[{"url":"https://github.com/sveltejs/devalue/security/advisories/GHSA-mwv9-gp5h-frr4","tags":[]},{"url":"https://www.vulncheck.com/advisories/sveltejs-devalue-before-5.6.4-prototype-injection-via-parse-and-unflatten","tags":[]}],"exploitRefs":[{"url":"https://github.com/sveltejs/devalue/security/advisories/GHSA-mwv9-gp5h-frr4","tags":[]}],"hasPoc":true,"ai":null}