CVE-2026-123563

8.7 highEPSS 0.4%Fix available

High (8.7) in sveltejs devalue. EPSS 0.4% estimated probability of exploitation activity in the next 30 days. Fixed in devalue 5.9.3.

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.

Severity

CVSS 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

CVSS 3.1

7.5 high

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

EPSS: 0.4% estimated probability of exploitation activity in the next 30 days; 32nd percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
CWE: CWE-789 Memory Allocation with Excessive Size Value
Published: 2026-11-08 02:16 UTC
NVD analysis: Awaiting analysis
Record from: the NVD, synced 2026-11-08 02:40 UTC

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Affected

sveltejs:devalue

Versions

From the CNA's record in the CVE List.

Product	Affected
sveltejs devalue	before 5.9.3

Packages (OSV)

Advisory	Ecosystem	Package	Affected	Fixed in
GHSA-r9w8-h9r3-54w4	npm	devalue	<5.9.3	5.9.3

References

Check your stack JSON