CVE-2026-123563
Devalue before 5.9.3 Typed-Array Allocation Validation Bypass via parse
Devalue before 5.9.3 contains a validation bypass vulnerability that allows custom ArrayBuffer revivers to skip typed-array allocation checks in the parse function. Attackers can supply very small crafted input processed by a malformed ArrayBuffer reviver to allocate massive ArrayBuffers, causing memory exhaustion and denial of service.
Fixes and workarounds
Fix
devalue (npm): OSV reports a fixed version 5.9.3. Check the advisory for supported release branches.
Source: OSV GHSA-r9w8-h9r3-54w4Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| devalue sveltejs devalue
npm |
≥ 0; < 5.9.3 (affected, semver) 5.9.3 (unaffected, semver) Other versions: unaffected |
CNA: VulnCheck |
devaluedevalue
npm |
≥ 0; < 5.9.3 (affected, semver); OSV events: introduced 0; fixed 5.9.3Source events (semver)Other versions: unaffected |
OSV GHSA-r9w8-h9r3-54w4 |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 8.7 high |
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 | CNA: VulnCheck |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA: VulnCheck |
| 4.0 / 8.7 high |
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD: [email protected] |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD: [email protected] |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/sveltejs/devalue/security/advisories/GHSA-r9w8-h9r3-54w4CNA: VulnCheck · vendor-advisory
- https://www.vulncheck.com/advisories/devalue-before-5.9.3-typed-array-allocation-validation-bypass-via-parseCNA: VulnCheck · third-party-advisory
- https://github.com/sveltejs/devalue/security/advisories/GHSA-r9w8-h9r3-54w4[email protected]
- https://www.vulncheck.com/advisories/devalue-before-5.9.3-typed-array-allocation-validation-bypass-via-parse[email protected]
- https://github.com/advisories/GHSA-r9w8-h9r3-54w4OSV / GitHub Security Advisories · advisory
- https://osv.dev/vulnerability/GHSA-r9w8-h9r3-54w4OSV / GitHub Security Advisories · osv
For agents and automation
Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.
Use the ontology-linked Cyber API with x402 pay per request, or a Y2 Pro or Elite API key with the intel:cyber scope.
Endpoints and access details
https://api.y2.dev/api/v2/cyber/cveshttps://api.y2.dev/api/v2/cyber/cves/{cveId}
A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.
For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.