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.
History

Sun, 08 Nov 2026 01:45:00 +0000

Type Values Removed Values Added
Description 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.
Title Devalue before 5.6.3 Denial of Service via Sparse Array Serialization
First Time appeared Svelte
Svelte devalue
Weaknesses CWE-770
CPEs cpe:2.3:a:svelte:devalue:*:*:*:*:*:*:*:*
Vendors & Products Svelte
Svelte devalue
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': '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'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-11-08T01:38:07.240Z

Updated: 2026-11-10T17:58:20.402Z

Reserved: 2026-11-06T00:53:14.312Z

Link: CVE-2026-123569

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-11-08T02:16:49.673

Modified: 2026-11-10T18:17:25.973

Link: CVE-2026-123569

cve-icon Redhat

No data.