CVE-2026-12208 jsonata-js jsonata Function Binding Frame System jsonata.js createFrame prototype pollution
Remote attackers can exploit prototype pollution in the jsonata-js library to execute arbitrary code or escalate privileges.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-12208?
CVE-2026-12208 is a medium-severity code injection vulnerability in jsonata-js jsonata, published on 15 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A weakness has been identified in jsonata-js jsonata up to 2.2.0. The affected element is the function createFrame of the file src/jsonata.js of the component Function Binding Frame System. This manipulation causes improperly controlled modification of object prototype attributes. It is possible to initiate the attack remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
Which versions are affected by CVE-2026-12208?
4 open source packages ship an affected version, including jsonata.
| Package | Affected | Fixed in |
|---|---|---|
jsonata npm | All versions | 1.8.8 |
jsonata npm | All versions | 1.8.8 |
jsonata npm | From 2.0.0 | 2.2.1 |
jsonata npm | From 2.0.0 | 2.2.1 |
How do I fix CVE-2026-12208?
Upgrade jsonata to a fixed version for your release line: 1.8.8 or 2.2.1.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-12208 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-12208 exists.
Sources
Also known as CLEANSTART-2026-VT69653, GHSA-663r-x48j-fg8p, MINI-7qwj-8rh4-8gh2, MINI-9jw8-cx4g-f2r9, MINI-m9wr-65fw-4h2r.