CVE-2026-44728 @babel/plugin-transform-modules-systemjs generates arbitrary code when compiling malicious input
Attackers can execute arbitrary code by crafting malicious JavaScript input processed by the Babel compiler's SystemJS module transform plugin.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-44728?
CVE-2026-44728 is a high-severity code injection vulnerability in @babel babel, published on 26 May 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Babel is a compiler for writing next generation JavaScript. From 7.12.0 to before 7.29.4 and 8.0.0-alpha.13, using Babel to compile code that was specifically crafted by an attacker can cause Babel to generate output code that executes arbitrary code. This vulnerability is fixed in 7.29.4 and 8.0.0-alpha.13.
Which versions are affected by CVE-2026-44728?
4 open source packages ship an affected version, including @babel/plugin-transform-modules-systemjs. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
@babel/plugin-transform-modules-systemjs npm | From 7.12.0 | 7.29.4 |
@babel/plugin-transform-modules-systemjs npm | From 7.12.0 | 7.29.4 |
@babel/plugin-transform-modules-systemjs npm | From 8.0.0-alpha.0 | 8.0.0-alpha.13 |
@babel/plugin-transform-modules-systemjs npm | From 8.0.0-alpha.0 | 8.0.0-alpha.13 |
Products include Babel Babel.
How do I fix CVE-2026-44728?
Upgrade @babel/plugin-transform-modules-systemjs to a fixed version for your release line: 7.29.4 or 8.0.0-alpha.13.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-44728 being exploited?
There is no known exploitation of CVE-2026-44728 in the wild and no public exploit code.
Other vulnerabilities in @babel babel
Sources
Also known as CLEANSTART-2026-GA82552, CLSA-2026-1784336946, CLSA-2026-1784509777, CLSA-2026-1784509815, CLSA-2026-1792160961, CLSA-2026-1792161418 and 271 more.