Description
Svelte devalue is a JavaScript library that serializes values into strings when JSON.stringify isn't sufficient for the job. From 5.3.0 to 5.6.1, certain inputs can cause devalue.parse to consume excessive CPU time and/or memory, potentially leading to denial of service in systems that parse input from untrusted sources. This affects applications using devalue.parse on externally-supplied data. The root cause is the typed array hydration expecting an ArrayBuffer as input, but not checking the assumption before creating the typed array. This vulnerability is fixed in 5.6.2.
Scores
CVSS v3
7.5
EPSS
0.0002
EPSS Percentile
5.2%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-405
Status
published
Products (2)
npm/devalue
5.3.0 - 5.6.2npm
svelte/devalue
5.3.0 - 5.6.2
Published
Jan 15, 2026
Tracked Since
Feb 18, 2026