Babel: Arbitrary File Read via sourceMappingURL Comment in @babel/core

Summary

CVE	CVE-2026-49356
State	PUBLISHED
Assigner	GitHub_M
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-06-22 18:16:41 UTC
Updated	2026-06-26 20:04:23 UTC
Description	Babel is a compiler for writing next generation JavaScript. Prior to 8.0.0-rc.6 and 7.29.6, @babel/core affected by an arbitrary file read via a sourceMappingURL comment. Using @babel/core to compile maliciously crafted code can allow an attacker to read any source map from the system that is running Babel, if the attacker controls the input source code, can read the output source code, and knows the path of the source map file that they want to read. This vulnerability is fixed in 8.0.0-rc.6 and 7.29.6.

Risk And Classification

Primary CVSS: v3.1 3.6 LOW from [email protected]

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N

EPSS: 0.001160000 probability, percentile 0.019050000 (date 2026-06-29)

Problem Types: CWE-22 | CWE-200 | CWE-22 CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') | CWE-200 CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Primary	3.6	LOW	`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N`
3.1	[email protected]	Secondary	3.2	LOW	`CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N`
3.1	CNA	DECLARED	3.2	LOW	`CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N`

CVSS v3.1 Breakdown

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

None

Availability

None

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N

NVD Known Affected Configurations (CPE 2.3)

Type	Vendor	Product	Version	Update	Edition	Language
Application	Babel	Babel	All	All	All	All
Application	Babel	Babel	8.0.0	alpha0	All	All
Application	Babel	Babel	8.0.0	alpha1	All	All
Application	Babel	Babel	8.0.0	alpha10	All	All
Application	Babel	Babel	8.0.0	alpha11	All	All
Application	Babel	Babel	8.0.0	alpha12	All	All
Application	Babel	Babel	8.0.0	alpha13	All	All
Application	Babel	Babel	8.0.0	alpha14	All	All
Application	Babel	Babel	8.0.0	alpha15	All	All
Application	Babel	Babel	8.0.0	alpha16	All	All
Application	Babel	Babel	8.0.0	alpha17	All	All
Application	Babel	Babel	8.0.0	alpha2	All	All
Application	Babel	Babel	8.0.0	alpha3	All	All
Application	Babel	Babel	8.0.0	alpha4	All	All
Application	Babel	Babel	8.0.0	alpha5	All	All
Application	Babel	Babel	8.0.0	alpha6	All	All
Application	Babel	Babel	8.0.0	alpha7	All	All
Application	Babel	Babel	8.0.0	alpha8	All	All
Application	Babel	Babel	8.0.0	alpha9	All	All
Application	Babel	Babel	8.0.0	beta0	All	All
Application	Babel	Babel	8.0.0	beta1	All	All
Application	Babel	Babel	8.0.0	beta2	All	All
Application	Babel	Babel	8.0.0	beta3	All	All
Application	Babel	Babel	8.0.0	beta4	All	All
Application	Babel	Babel	8.0.0	rc1	All	All
Application	Babel	Babel	8.0.0	rc2	All	All
Application	Babel	Babel	8.0.0	rc3	All	All
Application	Babel	Babel	8.0.0	rc4	All	All
Application	Babel	Babel	8.0.0	rc5	All	All

Vendor Declared Affected Products

Source	Vendor	Product	Version	Platforms
CNA	Babel	Babel	affected >= 8.0.0-alpha.0, < 8.0.0-rc.5	Not specified
CNA	Babel	Babel	affected < 7.29.6	Not specified

References

Reference	Source	Link	Tags
github.com/babel/babel/security/advisories/GHSA-4x5r-pxfx-6jf8	[email protected]	github.com	Mitigation, Vendor Advisory
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

No vendor comments have been submitted for this CVE.

There are currently no legacy QID mappings associated with this CVE.