Critical severity · published Aug 21, 2026
CVE-2026-77413
JSONata: Arbitrary Code Execution via crafted JSONata expressions
9.3
CVSS
0.7%
EPSS
No
On KEV
Description
JSONata is a JSON query and transformation language. Prior to 1.8.8 and 2.2.0, the src/functions.js lookup function lacked an Object.prototype.hasOwnProperty check and allowed crafted expressions to access inherited prototype members. An attacker able to supply an expression could use inherited prototype setters and getters, constructor access, valueOf, and process.getBuiltinModule to reach the child_process module and execute arbitrary code with the privileges of the host process. This issue is fixed in versions 1.8.8 and 2.2.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JS
jsonata · jsonata-js
< 2.2.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77413
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-77413
github.com
https://github.com/jsonata-js/jsonata/commit/4b217d514376e30cba278941298d7ba97c4a6c6e
github.com
https://github.com/jsonata-js/jsonata/commit/4c5f4adfb90a9b500889d50f90050ca68888b50d
github.com
https://github.com/jsonata-js/jsonata/pull/794
github.com
https://github.com/jsonata-js/jsonata/releases/tag/v1.8.8
github.com
https://github.com/jsonata-js/jsonata/releases/tag/v2.2.0
github.com
https://github.com/jsonata-js/jsonata/security/advisories/GHSA-8gq3-vp5j-2grp
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