Vulnerability library
Security checkFebruary 23, 2026

Feathers has an origin validation bypass via prefix matching

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Description

The origin validation uses startsWith() for comparison, allowing attackers to bypass the check by registering a domain that shares a common prefix with an allowed origin.

Recommendation

Update the @feathersjs/authentication-oauth package to the latest compatible version. Followings are version details:

  • Affected version(s): <= 5.0.39
  • Patched version(s): 5.0.40

References

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Related Issues

See something that needs correcting? Let us knowUpdated February 23, 2026