High 7.5Published Jun 9, 2026

CVE-2026-42570Svelte devalue: DoS via sparse array deserialization

Updated under an hour ago (Oct 27, 2026, 7:50 AM ET)

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Every CVE for sveltejs devalue

Exploited in the last 30 days

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.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-770
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Modified
Record last updated: Aug 24, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

sveltejs devalue sveltejs:devalue (from the name)	from 5.6.3, < 5.8.1	CNA record
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux	from 0:1.1.2-1.el10_2 not affected	CISA ADP
Red Hat Red Hat Trusted Artifact Signer 1.4 redhat:trusted_artifact_signer	from 1783327185 not affected	CISA ADP
Red Hat Red Hat Build of Podman Desktop redhat:podman_desktop	1	CISA ADP
svelte devalue svelte:devalue	from 5.6.3 before 5.8.1	NVD

References

References

https://github.com/sveltejs/devalue/security/advisories/GHSA-77vg-94rm-hx3p	x-refsource-confirm, vendor-advisory
https://github.com/sveltejs/devalue/commit/206ca6712fbc380a4571c59de9ab04b91110792d	x-refsource-misc, patch
https://github.com/sveltejs/devalue/releases/tag/v5.8.1	x-refsource-misc, product, release-notes
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

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.