X402

Security incidents tagged X402. Newest first.

1 X402 incident in the last 12 months

Critical 4 · High 3 · Med 2 · Low 1 · Update ½Severity-weighted: critical 4 · high 3 · medium 2 · low 1 · update ½LessMore

Patched
x402 SDK flaws could let malicious APIs drain AI agents' token balances
V12 disclosed 25 flaws in the x402 agent-payment SDKs, three rated critical: the default client had no spending limit (a hostile API could ask for an agent's whole token balance), the TypeScript Solana facilitator accepted token approvals as payments, and the SIWx login helper signed messages for other websites. All three were fixed in the August 18 releases, but no advisory was published, so npm audit and PyPI don't warn. Update @x402/fetch, @x402/axios, @x402/extensions and @x402/svm to 2.23.0 or later.
x402 SDKs (TypeScript @x402/*, Python x402, Go)Since Oct 22, 2026updated Oct 23, 2026, 11:25 UTC

x402 SDK flaws could let malicious APIs drain AI agents' token balances
The Hacker News
@TheHackersNews
🚨 A malicious API could drain an AI agent's token balance via an x402 SDK flaw. V12 rated 3 bugs critical: — No default spending cap — Solana approvals passed as payments — Logins signed for other sites All patched. No advisory, so npm audit & PyPI miss them. Read more ↓ t.co/b455EukyKw
Oct 23, 2026view on x
x402 SDK flaws could let malicious APIs drain AI agents' token balances
V12
@v12sec
V12 found 25 vulnerabilities in the x402 protocol. Critical findings included: - Requests approved without any payment - Maliciously high requests being paid by default - Session takeover from relayed login signatures Here's how. 🧵 t.co/0jIv7VpET7
Oct 22, 2026view on x