GHSA-4x5r-pxfx-6jf8

@babel/core: Arbitrary File Read via sourceMappingURL Comment

At a glance

Published
Updated
CVE
CVE-2026-49356
CVSS_V3
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N

Description

## Impact Using `@babel/core` to compile maliciously crafted code can allow ab attacker to read any source map from the system that is running Babel, if these conditions are _all_ true: - the attacker controls the input source code - the attacker can read the output source code - the attacker knows the path of the source map file that they want to read **Users that only compile trusted code are not impacted.** ## Patches The vulnerability has been fixed in `@babel/core@7.29.6` and `@babel/core@8.0.0-rc.6`. ## Workarounds Callers can mitigate the issue without upgrading by setting [`inputSourceMap: false`](https://babeljs.io/docs/options#inputsourcemap) in their Babel options. Callers can also manually extract the `#sourceMappingURL` comment from the input source code, validate whether the source map that it links to is allowed to be read, and if it is pass an object to `inputSourceMap` (passing `false` when it's not). ## Credits Thanks Teodor-Cristian Radoi for reporting the vulnerability.

Affected packages

PackageVersions
npm · @babel/coreintroduced 8.0.0-alpha.0, fixed 8.0.0-rc.6
npm · @babel/coreintroduced 0, fixed 7.29.6

References

Sources

SourceLicence
OSV.devCC-BY 4.0 — GitHub Advisory Database