Advisories for Npm/Mppx package

2026

mppx: Gas Draining with padding

A malicious client can force the server to pay ~5x the normal transaction fee. This dramatically increases operational costs and completely destroys the profit margin on low-cost items. Please provide a way to share the PoC in .zip format to you. Thank you!

mppx has Stripe charge credential replay via missing idempotency check

The stripe/charge payment method did not check Stripe's Idempotent-Replayed response header when creating PaymentIntents. An attacker could replay a valid credential containing the same spt token against a new challenge, and the server would accept the replayed Stripe PaymentIntent as a new successful payment without actually charging the customer again. This allowed an attacker to pay once and consume unlimited resources by replaying the credential.

mppx has multiple payment bypass and griefing vulnerabilities

Multiple vulnerabilities were discovered in tempo/charge and tempo/session which allowed for undesirable behaviors, including: Replaying tempo/charge transaction hashes across push/pull modes, across charge/session endpoints, and via concurrent requests Performing free tempo/charge requests due to missing transfer log verification in pull-mode Replaying tempo/charge credentials across routes via cross-route scope confusion (memo/splits not included in scope binding) Manipulating the fee payer of a tempo/charge handler into paying for requests (missing sender signature …