mppx is a TypeScript interface for machine payments protocol.

Code

The project this record applies to. Exploit listings stay in References.

• Repository · github.com

Timeline

Detection, updates, and resolution for this record.

1. Mar 31, 2026 · NIST NVD

   Detected

   mppx is a TypeScript interface for machine payments protocol. Prior to version 0.4.11, the tempo/session cooperative close handler validated the close voucher amount using "<" instead of "<=" against the on-chain settled amount. An attacker could submit a close voucher exactly equal to the settled amount, which would be accepted without committing any new funds, effectively closing or griefing the

2. Jul 24, 2026 · NIST NVD

   Updated

   mppx is a TypeScript interface for machine payments protocol. Prior to version 0.4.11, the tempo/session cooperative close handler validated the close voucher amount using "<" instead of "<=" against the on-chain settled amount. An attacker could submit a close voucher exactly equal to the settled amount, which would be accepted without committing any new funds, effectively closing or griefing the

Affected

• cpe wevm/mppxversion unspecified

Sources

• CVE.orgVulnerability recordCVE-2026-34209

  Official CVE identifier

  cve.org
• NIST NVDVulnerability recordCVE-2026-34209

  mppx is a TypeScript interface for machine payments protocol. Prior to version 0.4.11, the tempo/session cooperative close handler validated the close voucher amount using "<" instead of "<=" against the on-chain settled amount. An attacker could submit a close voucher exactly eq

  nvd.nist.gov

References

• Patch · github.com
• Release Notes · github.com
• Patch · github.com