Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.277 ·

Session/checkout ID format tightened to a strict UUID regex

Device attestation status now validates session/checkout IDs as strict UUIDs

TierUnder the hoodhow much it should matter to you
Useful1my rating, 1 to 5
Signal1worth watching, 1 to 5
AreaAttestationwhat it touches
KindInternal Changesin v2.1.277,
Under the hood

Device attestation status now validates session/checkout IDs as strict UUIDs

What

A constant used in device attestation status checks, which previously matched an ID by string prefix, is replaced with a strict regular expression that only matches a properly formatted UUID (a standard 36-character identifier format).

Why

This makes the check stricter: an ID has to be a well-formed UUID to pass, rather than merely starting with the right prefix, which should reduce the chance of a malformed or spoofed ID being accepted.

See this entry in the whole of v2.1.277 →