CVE-2026-42570
Medium
Elevated severity or exploit probability.
CVSS base
7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS — probability of exploitation (30 days)
0.7%
51.8th percentile
CISA KEV
Not listed
Weakness / dates
CWE-770
Published 2026-06-09 · modified 2026-08-24
Description
Svelte devalue is a JavaScript library that serializes values into strings when JSON.stringify isn't sufficient for the job. From version 5.6.3 to before version 5.8.1, devalue.parse could, due to quirks in some JavaScript engines, be convinced to allocate much more memory than was needed when deserializing sparse arrays, leading to excessive memory consumption. This issue has been patched in version 5.8.1.
Affected
References
- https://github.com/sveltejs/devalue/commit/206ca6712fbc380a4571c59de9ab04b91110792d
- https://github.com/sveltejs/devalue/releases/tag/v5.8.1
- https://github.com/sveltejs/devalue/security/advisories/GHSA-77vg-94rm-hx3p
- https://access.redhat.com/errata/RHSA-2026:37272
- https://access.redhat.com/errata/RHSA-2026:57590
- https://access.redhat.com/security/cve/CVE-2026-42570
- https://bugzilla.redhat.com/show_bug.cgi?id=2487050
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42570.json