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All of v2.1.251 Home All releases olderv2.1.250
Claude Code v2.1.251

Sessions authenticated through a gateway attach a pinned identity

Under the hood
Useful2 Signal3
Auth

Gateway-authenticated sessions now attach a pinned identity tying them to one gateway origin.

What

Accounts that authenticate through a gateway token now send a consent identity and a pinned fingerprint alongside the usual authorization header, tying the session to one specific gateway origin. The identity is built from a fixed gateway: tag plus the gateway's https origin, and the account identifier is hashed with SHA-256 once it passes a length threshold rather than being sent as-is.

Details
  • only applies when gateway token auth is in use; API key and OAuth sessions keep their existing consent identity path
  • the hashing means the raw account identifier does not travel in the header
Evidence

gateway:, organizationUuid: ${pe}${o}#${t}``

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

See this entry in the whole of v2.1.251 →