{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-123565", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-11-06T00:53:14.312Z", "datePublished": "2026-11-08T01:38:04.469Z", "dateUpdated": "2026-11-08T01:38:04.469Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-11-08T01:38:04.469Z"}, "datePublic": "2026-09-18T00:00:00.000Z", "title": "Devalue before 5.9.3 Quadratic Expansion Denial of Service via uneval", "descriptions": [{"lang": "en", "value": "Sveltejs devalue before 5.9.3 contains a resource exhaustion vulnerability where repeated primitive strings cause quadratic expansion in the uneval function. Attackers can supply a small crafted payload that is parsed and then passed to uneval, producing a very large serialized string that exhausts memory or CPU."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Uncontrolled Resource Consumption", "cweId": "CWE-400", "type": "CWE"}]}], "affected": [{"vendor": "sveltejs", "product": "devalue", "defaultStatus": "unaffected", "packageURL": "pkg:npm/devalue", "versions": [{"version": "0", "status": "affected", "versionType": "semver", "lessThan": "5.9.3"}, {"version": "5.9.3", "status": "unaffected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:svelte:devalue:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.9.3"}]}]}], "metrics": [{"cvssV4_0": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "baseScore": 8.7, "baseSeverity": "HIGH", "exploitMaturity": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "format": "CVSS"}, {"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "format": "CVSS"}], "references": [{"url": "https://github.com/sveltejs/devalue/security/advisories/GHSA-mcm9-63f2-9j32", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-mcm9-63f2-9j32)"}, {"name": "VulnCheck Advisory: Devalue before 5.9.3 Quadratic Expansion Denial of Service via uneval", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/devalue-before-5.9.3-quadratic-expansion-denial-of-service-via-uneval"}], "credits": [{"lang": "en", "value": "elliott-with-the-longest-name-on-github", "type": "remediation developer"}], "x_generator": {"engine": "vulncheck-endgame"}}}}

{}

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{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,5.9.3)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "5.9.3"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "devalue", "source": "cna", "vendor": "sveltejs"}, "product": "devalue", "vendor": "svelte"}], "created": "2026-11-08T03:15:08.466973+00:00", "updated": "2026-11-08T04:15:14.443447+00:00", "vendors": ["svelte", "svelte$PRODUCT$devalue"]}