CVE-2026-77413 — jsonata
Fix: jsonata-js/jsonata@4b217d5CVE-2026-77413 is a Code Injection vulnerability in jsonata. A fix is available for jsonata — see the affected versions and patch details below.
JSONata: Arbitrary Code Execution via crafted JSONata expressions
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-77413.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
jsonatanpmDescription
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | jsonata | all versions | 1.8.8npm install jsonata@1.8.8 |
| 📦npm | jsonata | ≥ 2.0.0&&< 2.2.0 | 2.2.0npm install jsonata@2.2.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for jsonata, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update jsonata to 1.8.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-77413 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This is a Critical arbitrary code execution flaw in the JSONata library, affecting its `lookup` function due to improper object property validation. An attacker supplying crafted JSONata expressions to a vulnerable Red Hat product could achieve remote code execution with the privileges of the host process, leading to…
To mitigate this issue, applications utilizing the JSONata library should be configured to strictly validate and sanitize all incoming JSONata expressions, ensuring that only trusted and well-formed expressions are processed. If processing untrusted expressions is unavoidable, deploy the application in a sandboxed environment with minimal privileges to limit the potential impact of arbitrary code execution.Source: Red Hat security advisory for CVE-2026-77413 (CC BY 4.0)
Frequently Asked Questions
Is CVE-2026-77413 in your dependencies?
Find it across npm, including transitive dependencies.