Zod can exhaust memory while validating oversized constrained collections

published 2026-10-01 last mo. modified 2026-10-23 19d ago also CVE-2023-54404

cvss: 7.5; version 3.1, GitHub
cisa kev: Not listed; not in CISA's catalog
epss: —; no score, EPSS covers CVEs only
public exploits: 0; none known

Zod schema-validation library through 4.6.5 contains an uncontrolled resource consumption vulnerability that allows attackers to exhaust memory by submitting a large array to an application using an array schema without a length constraint. Attackers can exploit the handleArrayResult parse logic in $ZodArray, which accumulates every validation issue for each failing element with no cap or early termination, causing the process to allocate excessive issue objects and crash due to out-of-memory conditions.

Patch / fix

fixed in 1 links 3

npm zod 4.6.6

github.com/colinhacks/zod@a0ebf97 commit
github.com/colinhacks/zod#6475 pull request
github.com/colinhacks/zod#6652 pull request

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CVSS scores

assigned by	version	score	vector
GitHub	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem	package	affected	fixed in
npm	zod	<4.6.6	4.6.6

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

GitHub Advisory GHSA-mrhx-c7xc-m3w5

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