---
id: CVE-2026-123563
title: Devalue before 5.9.3 Typed-Array Allocation Validation Bypass via parse
summary: >-
  Devalue before 5.9.3 contains a validation bypass vulnerability that allows
  custom ArrayBuffer revivers to skip typed-array allocation checks in the parse
  function. Attackers can supply very small crafted input processed by a
  malformed A…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-789
vendor: sveltejs
product: devalue
affected:
  - devalue < 5.9.3
published: '2026-11-08'
updated: '2026-11-08'
sourceUpdated: '2026-11-08T01:38:03.120Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-123563'
references:
  - url: >-
      https://github.com/sveltejs/devalue/security/advisories/GHSA-r9w8-h9r3-54w4
    label: GitHub Security Advisory (GHSA-r9w8-h9r3-54w4)
  - url: >-
      https://www.vulncheck.com/advisories/devalue-before-5.9.3-typed-array-allocation-validation-bypass-via-parse
    label: >-
      VulnCheck Advisory: Devalue before 5.9.3 Typed-Array Allocation Validation
      Bypass via parse
tags:
  - cve.org
ingestedAt: '2026-11-08T02:43:18.661Z'
---

## Overview

Devalue before 5.9.3 contains a validation bypass vulnerability that allows custom ArrayBuffer revivers to skip typed-array allocation checks in the parse function. Attackers can supply very small crafted input processed by a malformed ArrayBuffer reviver to allocate massive ArrayBuffers, causing memory exhaustion and denial of service.

## Affected

- `devalue < 5.9.3`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.