Resource exhaustion in Sveltejs Devalue

CVE-2026-81176

Svelte devalue is a JavaScript library that serializes values into strings when JSON.stringify isn't sufficient for the job. Prior to 5.9.2, devalue.parse does not reject out-of-bounds indices that are greater than or equal to values.length in src/parse.js. A specially crafted untrusted payload can make the parser alternate between array representations, producing quadratic work as the payload grows and causing denial of service in applications that parse untrusted devalue data. This issue is fixed in version 5.9.2.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.005 (43.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-81176: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-81176?
CVE-2026-81176 is a medium-severity vulnerability in Sveltejs Devalue, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.3/10. Published 2026-09-16.
How severe is CVE-2026-81176?
Medium severity. CVSS v3 base score is 5.3 out of 10.