{"dataType": "CVE_RECORD", "dataVersion": "5.1", "cveMetadata": {"cveId": "CVE-2025-62494", "assignerOrgId": "14ed7db2-1595-443d-9d34-6215bf890778", "state": "PUBLISHED", "assignerShortName": "Google", "dateReserved": "2025-10-15T08:47:41.878Z", "datePublished": "2025-10-16T15:51:50.977Z", "dateUpdated": "2025-10-16T17:46:39.174Z"}, "containers": {"cna": {"affected": [{"collectionURL": "https://bellard.org/quickjs/", "defaultStatus": "unaffected", "packageName": "JS_ConcatStringInPlace", "product": "QuickJS", "vendor": "QuickJS", "versions": [{"lessThan": "2025-09-13", "status": "affected", "version": "2025-04-26", "versionType": "date"}]}], "credits": [{"lang": "en", "type": "finder", "value": "Google Big Sleep"}], "datePublic": "2025-07-24T22:00:00.000Z", "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>A type confusion vulnerability exists in the handling of the <b>string addition (<code>+</code>) operation</b> within the QuickJS engine.</p><ol><li><p>The code first checks if the <b>left-hand operand</b> is a <b>string</b>.</p></li><li><p>It then attempts to convert the <b>right-hand operand</b> to a primitive value using <code>JS_ToPrimitiveFree</code>. 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