Log in Start free

Vulnerability · Published Aug 21, 2026 · Assigned by GitHub_M

CVE-2026-77415JSONata: Arbitrary Code Execution via crafted JSONata expressions

Critical 9.3

In plain English

A critical-severity code injection in jsonata from jsonata-js. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 60% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)9.3Critical
Exploit odds (30 days)0.9%top 40.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

JSONata is a JSON query and transformation language. Prior to 1.8.8 and 2.2.1, crafted JSONata expressions could chain several object-integrity weaknesses to execute arbitrary code. The chain could overwrite $clone to mutate objects through evaluateTransformExpression, expose and deconstruct JSONata functions or lambdas through $merge.*, replace proc.arguments.forEach used by applyProcedure, and forge internal lambda state. These primitives allowed an attacker to reach prototype getters, prototype and constructor access, and process.getBuiltinModule with child_process, executing code with the privileges of the host process. This issue is fixed in versions 1.8.8 and 2.2.1.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
npmjsonata2.2.1GHSA-66mm-25pp-rfff
npmjsonata1.8.8GHSA-66mm-25pp-rfff

Affected products (as reported)

VendorProductVersions
jsonata-js jsonata < 1.8.8>= 2.0.0, < 2.2.1

Weakness: CWE-94 · Vector: 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

References