Details

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 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.

Severity

• CVSS Score: 3.2 / 10 (Low)
• Vector String: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N

References

• https://github.com/babel/babel/security/advisories/GHSA-4x5r-pxfx-6jf8
• https://babeljs.io/docs/options#inputsourcemap
• https://github.com/advisories/GHSA-4x5r-pxfx-6jf8

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

v7.29.6

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v7.29.6 (2026-05-25)

🐛 Bug Fix

• babel-generator
  • #​18014 Catchup source map position in preserveFormat (@​nicolo-ribaudo)
• babel-core
  • #​18001 [7.x packport]Improve input source map handling (@​JLHwung)
• babel-core, babel-generator
  • #​17998 Preserve original identifier names from input sourcemaps (#​17992) (@​Andarist)

Committers: 3

• Huáng Jùnliàng (@​JLHwung)
• Mateusz Burzyński (@​Andarist)
• Nicolò Ribaudo (@​nicolo-ribaudo)

v7.29.0

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v7.29.0 (2026-01-31)

Thanks @​simbahax for your first PR!

🚀 New Feature

• babel-types
  • #​17750 [7.x backport] Add attributes import declaration builder (@​JLHwung)
• babel-standalone
  • #​17663 [7.x backport] feat(standalone): export async transform (@​JLHwung)
  • #​17725 [7.x backport] feat: read standalone targets from data-targets (@​JLHwung)

🐛 Bug Fix

• babel-parser
  • #​17765 fix(parser): correctly parse type assertions in extends clause (@​nicolo-ribaudo)
  • #​17723 [7.x backport] fix(parser): improve super type argument parsing (@​JLHwung)
• babel-traverse
  • #​17708 fix(traverse): provide a hub when traversing a File or Program and no parentPath is given (@​simbahax)
• babel-plugin-transform-block-scoping, babel-traverse
  • #​17737 [7.x backport] fix: Rename switch discriminant references when body creates shadowing variable (@​magic-akari)

🏃‍♀️ Performance

• babel-generator, babel-runtime-corejs3
  • #​17642 [Babel 7] Improve generator performance (@​liuxingbaoyu)

Committers: 6

• David (@​simbahax)
• Huáng Jùnliàng (@​JLHwung)
• Nicolò Ribaudo (@​nicolo-ribaudo)
• @​liuxingbaoyu
• @​magic-akari

v7.28.6

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v7.28.5

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👓 Spec Compliance

• babel-parser
  • #​17446 Allow Runtime Errors for Function Call Assignment Targets (@​liuxingbaoyu)
• babel-helper-validator-identifier
  • #​17501 fix: update identifier to unicode 17 (@​fisker)

🐛 Bug Fix

• babel-plugin-proposal-destructuring-private
  • #​17534 Allow mixing private destructuring and rest (@​CO0Ki3)
• babel-parser
  • #​17521 Improve @babel/parser error typing (@​JLHwung)
  • #​17491 fix: improve ts-only declaration parsing (@​JLHwung)
• babel-plugin-proposal-discard-binding, babel-plugin-transform-destructuring
  • #​17519 fix: rest correctly returns plain array (@​liuxingbaoyu)
• babel-helper-create-class-features-plugin, babel-helper-member-expression-to-functions, babel-plugin-transform-block-scoping, babel-plugin-transform-optional-chaining, babel-traverse, babel-types
  • #​17503 Fix JSXIdentifier handling in isReferencedIdentifier (@​JLHwung)
• babel-traverse
  • #​17504 fix: ensure scope.push register in anonymous fn (@​JLHwung)

🏠 Internal

• babel-types
  • #​17494 Type checking babel-types scripts (@​JLHwung)

🏃‍♀️ Performance

• babel-core
  • #​17490 Faster finding of locations in buildCodeFrameError (@​liuxingbaoyu)

v7.28.4

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🏠 Internal

• babel-core, babel-helper-check-duplicate-nodes, babel-traverse, babel-types
  • #​17493 Update Jest to v30.1.1 (@​JLHwung)
• babel-plugin-transform-regenerator
  • #​17455 chore: Clean up transform-regenerator (@​liuxingbaoyu)
• babel-core
  • #​17474 Switch to @​jridgewell/remapping (@​mrginglymus)