Preliminary research

When HTTP 402 Meets the Blockchain: Risks on Emerging x402 Payments

Qinying Wang, Yong Yang, Yuan Chen, Shouling Ji and Mathias Payer · USENIX

AI-collected research leads through 6 October 2026, including bounded month-by-month reviews of selected social and community sources from January through September. Unranked, incomplete, not community-vetted, and subject to change.

x402 extends HTTP 402 with a payment negotiation flow and delegates proof verification and on-chain settlement to third-party facilitators, so one facilitator becomes shared payment infrastructure for many independent merchants and one flaw reaches all of them. Eight authorization and execution-safety rules are derived and checked against deployments already carrying real mainnet volume.

Record

Researcher

Qinying Wang, Yong Yang, Yuan Chen, Shouling Ji and Mathias Payer

Published by

USENIX

In the archive

• Collected in the 2026 preliminary research sweep

Related sources

• Paper
• Tool

Tags

• http
• blockchain
• rest-api
• ai-agent
• auth-bypass
• measurement-study
• owasp-a01-2021

This page is the archive's own catalogue record. The research is the work of Qinying Wang, Yong Yang, Yuan Chen, Shouling Ji and Mathias Payer, first published at the original source. Preserved copies are kept so the citation survives its host.