What is CVE-2024-27307?

CVE-2024-27307 is a critical-severity vulnerability in Jsonata, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 9.8/10. Published 2024-03-06.

How severe is CVE-2024-27307?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Prototype Pollution in Jsonata

CVE-2024-27307

JSONata is a JSON query and transformation language. Starting in version 1.4.0 and prior to version 1.8.7 and 2.0.4, a malicious expression can use the transform operator to override properties on the `Object` constructor and prototype. This may lead to denial of service, remote code execution or other unexpected behavior in applications that evaluate user-provided JSONata expressions. This issue has been fixed in JSONata versions 1.8.7 and 2.0.4. Applications that evaluate user-provided expressions should update ASAP to prevent exploitation. As a workaround, one may apply the patch manually.

Vulnerability class: Prototype Pollution

Published 2024-03-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.014 (72.7th percentile), scored 2026-10-23.

Low probability of exploitation in the next 30 days, but still tracked. 73rd percentile — 72.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

Jsonata
Jsonata-Js Jsonata — versions >= 1.4.0, < 1.8.7, >= 2.0.0, < 2.0.4

Weakness classification (CWE)

CWE-1321 — Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution)

References

github.com/jsonata-js/jsonata/security/advisories/GHSA-fqg8-vfv7-8fj8 (Vendor Advisory, Technical Description)
github.com/jsonata-js/jsonata/commit/1d579dbe99c19fbe509f5ba2c6db7959b0d456d1 (Patch)
github.com/jsonata-js/jsonata/commit/335d38f6278e96c908b24183f1c9c90afc8ae00c (Patch)
github.com/jsonata-js/jsonata/commit/c907b5e517bb718015fcbd993d742ba6202f2be2 (Patch)
github.com/jsonata-js/jsonata/releases/tag/v2.0.4 (Product, Release Notes)

Frequently asked questions

What is CVE-2024-27307?: CVE-2024-27307 is a critical-severity vulnerability in Jsonata, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 9.8/10. Published 2024-03-06.
How severe is CVE-2024-27307?: Critical severity. CVSS v3 base score is 9.8 out of 10.