CVE-2026-70658 pay-rails/pay: non-constant-time HMAC comparison in Paddle Billing webhook signature verifier

Pay is a payments engine for Ruby on Rails 6.0 and higher. Prior to 11.6.2, Pay::Webhooks::PaddleBillingControllervalidsignature? in app/controllers/pay/webhooks/paddlebillingcontroller.rb compares the computed 64-character SHA-256 HMAC with the attacker-controlled h1 token from the...