CVE-2026-123569

CVSS 8.7 (high) · published 2026-11-08

The devalue package for npm before 5.6.3 can consume excessive CPU and memory when serializing sparse arrays with uneval or stringify. An attacker who manages to get a sparse array created on the server, which mainstream wire formats do not allow, and serialized there can cause a denial of service.

Weakness: CWE-770

Source: NVD CVE-2026-123569

References

• https://github.com/sveltejs/devalue/security/advisories/GHSA-33hq-fvwr-56pm
• https://www.vulncheck.com/advisories/devalue-before-5.6.3-denial-of-service-via-sparse-array-serialization

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