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AWS cognito medium security documentation change

Service: cognito · 2026-06-25 · Security-related medium

File: cognito/latest/developerguide/cognito-terms.md

Summary

Clarified UUID format expectations and validation guidance

Security assessment

Explicitly warns against strict UUID format validation to prevent potential authentication/authorization failures

Diff

diff --git a/cognito/latest/developerguide/cognito-terms.md b/cognito/latest/developerguide/cognito-terms.md
index ac95bc15e..ee68770f9 100644
--- a//cognito/latest/developerguide/cognito-terms.md
+++ b//cognito/latest/developerguide/cognito-terms.md
@@ -142 +142 @@ An IdP to a user pool or identity pool that generates digitally signed assertion
-A 128-bit label that is applied to an object. Amazon Cognito UUIDs are unique per user pool or identity pool, but don't conform to a specific UUID format.
+A 128-bit label that is applied to an object. Amazon Cognito UUIDs are unique per user pool or identity pool, but don't conform to a specific UUID format, including RFC UUID. You shouldn't strictly validate the format of Amazon Cognito identifiers.