CVE-2026-34210 mppx has Stripe charge credential replay via missing idempotency check
Attackers can replay payment credentials to consume unlimited resources without paying, affecting users of the mppx TypeScript library.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-34210?
CVE-2026-34210 is a medium-severity vulnerability in wevm mppx, published on 31 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
mppx is a TypeScript interface for machine payments protocol. Prior to version 0.4.11, 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. This issue has been patched in version 0.4.11.
Weakness: CWE-697
Which versions are affected by CVE-2026-34210?
2 open source packages ship an affected version, including mppx. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mppx npm | All versions | 0.4.11 |
mppx npm | All versions | 0.4.11 |
Products include Wevm Mppx.
How do I fix CVE-2026-34210?
Upgrade mppx to 0.4.11 or later.
Is CVE-2026-34210 being exploited?
There is no known exploitation of CVE-2026-34210 in the wild and no public exploit code.
Other vulnerabilities in wevm mppx
Sources
Also known as GHSA-8mhj-rffc-rcvw.