# CVE-2026-52746: jsonata-js JSONata Denial of Service in $toMillis function

Source: https://junglewise.ai/threats/cve-2026-52746-jsonata-js-jsonata-denial-of-service-in-tomillis-function  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-17. Updated: 2026-07-17  
License: CC BY 4.0 with a link back

CVE-2026-52746 · Severity: high · CVSS 7.5 · Published 2026-07-17

JSONata is a popular library used to query and transform data. A flaw in how it processes date and time information allows an attacker to send specially crafted inputs that cause the system to freeze or crash. This can lead to a total service outage for any application that allows users to provide their own data transformation rules.

Technologies: [JSONata](https://junglewise.ai/threats/technologies/jsonata), [jsonata (npm)](https://junglewise.ai/threats/technologies/npm-jsonata). Vendors: [JSONata](https://junglewise.ai/threats/vendors/jsonata), [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-52746 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-52746 being exploited in the wild.

**How severe is CVE-2026-52746?** High severity, with a CVSS score of 7.5, published 17 July 2026.

**Which products and versions are affected?** JSONata < 2.2.0; jsonata (npm) SEMVER:introduced=2.0.0,fixed=2.2.0.

**Is there a fix for CVE-2026-52746?** Yes. jsonata (npm): upgrade to 2.2.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-52746 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-52746?** Check whether you run JSONata or jsonata (npm) 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

- jsonata (npm): upgrade to 2.2.0 or later

  ```sh
  npm install jsonata@2.2.0
  ```


## Technical details

A Regular Expression Denial of Service (ReDoS) vulnerability exists in JSONata versions prior to 2.2.0. The root cause is inefficient regex complexity (CWE-1333) within the ISO-8601 validation logic used by the $toMillis function. Specifically, the 'iso8601regex' pattern contained overlapping or poorly constrained groups that triggered superlinear backtracking when processing certain non-matching strings. An unauthenticated remote attacker can exploit this by providing a malicious expression or input string to an application that evaluates user-supplied JSONata queries. This results in high CPU consumption and a denial-of-service condition. The issue was resolved in version 2.2.0 by optimizing the regex pattern.

## Affected products

- jsonata-js JSONata < 2.2.0

## Identifiers

- CVE-2026-52746
- GHSA-86vw-mfpg-wwv9

## Timeline

- 2026-04-30: other: Initial fix for $toMillis fractional seconds merged
- 2026-05-14: patched: Version 2.2.0 released with ISO8601 regex fix
- 2026-05-29: advisory: GitHub Security Advisory published
- 2026-07-17: disclosed: CVE published to NVD

## References

- [https://github.com/jsonata-js/jsonata/commit/80ba95d170f74e3f20f4f36b8b77d8c85cea7686](https://github.com/jsonata-js/jsonata/commit/80ba95d170f74e3f20f4f36b8b77d8c85cea7686)
- [https://github.com/jsonata-js/jsonata/commit/d6ffc17cb16a8e53c222205bd274624e919cce0b](https://github.com/jsonata-js/jsonata/commit/d6ffc17cb16a8e53c222205bd274624e919cce0b)
- [https://github.com/jsonata-js/jsonata/pull/782](https://github.com/jsonata-js/jsonata/pull/782)
- [https://github.com/jsonata-js/jsonata/pull/793](https://github.com/jsonata-js/jsonata/pull/793)
- [https://github.com/jsonata-js/jsonata/releases/tag/v2.2.0](https://github.com/jsonata-js/jsonata/releases/tag/v2.2.0)
- [https://github.com/jsonata-js/jsonata/security/advisories/GHSA-86vw-mfpg-wwv9](https://github.com/jsonata-js/jsonata/security/advisories/GHSA-86vw-mfpg-wwv9)

## Related threats

- [JSONata arbitrary code execution via crafted expressions](https://junglewise.ai/threats/cve-2026-77415-jsonata-arbitrary-code-execution-via-crafted-expressions)
- [JSONata arbitrary code execution via expression injection](https://junglewise.ai/threats/cve-2026-77414-jsonata-arbitrary-code-execution-in-expression-evaluation)
- [JSONata arbitrary code execution in lookup function](https://junglewise.ai/threats/cve-2026-77413-jsonata-arbitrary-code-execution-in-lookup-function)
- [JSONata prototype pollution in createFrame function](https://junglewise.ai/threats/cve-2026-12208-jsonata-prototype-pollution-in-createframe-function)
- [JSONata prototype pollution via transform operator](https://junglewise.ai/threats/cve-2024-27307-jsonata-prototype-pollution-via-transform-operator)