# CVE-2023-54404: Zod schema-validation library uncontrolled resource consumption

Source: https://junglewise.ai/threats/cve-2023-54404-zod-schema-validation-library-through-4-6-5-contains-an  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-01. Updated: 2026-10-05  
License: CC BY 4.0 with a link back

CVE-2023-54404 · Severity: high · CVSS 7.5 · Published 2026-10-01

Zod is a schema-validation library used by applications to validate user input and data. A denial-of-service vulnerability allows attackers to crash an application by sending a large array to a field that uses an unconstrained array schema, exhausting the server's memory and causing it to stop responding.

Technologies: [Colin McDaniel Zod](https://junglewise.ai/threats/technologies/zod). Vendors: [Colin McDaniel](https://junglewise.ai/threats/vendors/colin-mcdaniel).

## Quick answers

**Is CVE-2023-54404 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2023-54404 being exploited in the wild.

**How severe is CVE-2023-54404?** High severity, with a CVSS score of 7.5, published 1 October 2026.

**Which products and versions are affected?** Colin McDaniel Zod through 4.6.5; Zod < 4.6.6, SEMVER:introduced=0,fixed=4.6.6.

**Is there a fix for CVE-2023-54404?** Yes. Zod: upgrade to 4.6.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2023-54404 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2023-54404?** Check whether you run Colin McDaniel Zod or Zod at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Zod: upgrade to 4.6.6 or later

## Technical details

The vulnerability exists in the handleArrayResult parse logic of $ZodArray, which accumulates validation issues for each failing array element without a limit or early termination mechanism. An attacker can exploit this by submitting a large array input, causing the application to allocate excessive issue objects and crash due to out-of-memory conditions. The issue affects Zod through version 4.6.5 and can be mitigated or fixed by implementing an abortEarly parse option.

## Affected products

- Colin McDaniel Zod through 4.6.5

## Identifiers

- CVE-2023-54404
- GHSA-mrhx-c7xc-m3w5

## Timeline

- 2026-10-01: disclosed

## References

- [https://github.com/colinhacks/zod/issues/1872](https://github.com/colinhacks/zod/issues/1872)
- [https://github.com/colinhacks/zod/pull/6475](https://github.com/colinhacks/zod/pull/6475)

## Related threats

- [Zod email validation regular expression denial of service](https://junglewise.ai/threats/cve-2023-4316-zod-email-validation-regular-expression-denial-of-service)