CVE-2026-77414: Jsonata-Js Jsonata

Critical severity, CVSS 9.3. EPSS: 0.6% chance of exploitation in the next 30 days.

JSONata is a JSON query and transformation language. Prior to 1.8.8 and 2.2.1, the src/jsonata.js environment.lookup function used a bypassable hasOwnProperty check. Crafted expressions could use $hasOwnProperty, $spread, $string, prototype access, and $constructor to reach the object prototype and invoke process.getBuiltinModule with child_process, executing arbitrary code with the privileges of the host process. This issue is fixed in versions 1.8.8 and 2.2.1.

Affected products

• Jsonata-Js Jsonata: before 1.8.8 (fixed in 1.8.8); from 2.0.0, before 2.2.1 (fixed in 2.2.1)

Published 2026-08-21. Last modified 2026-09-09.