Vulnerability library
Security checkJanuary 16, 2026

Sandbox Breakout / Arbitrary Code Execution in localeval

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High severitynpmlocaleval

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Description

All versions of localeval are vulnerable to Sandbox Escape leading to Remote Code Execution. The package fails to restrict access to the main context through constructor.constructor. This may allow attackers to execute arbitrary code in the system. Evaluating the payload

returns the contents of process.env.

Recommendation

Update the localeval package to the latest compatible version. Followings are version details:

  • Affected version(s): >= 0, < 15.3.0
  • Patched version(s): 15.3.0

References

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See something that needs correcting? Let us knowUpdated January 16, 2026