Vulnerability Description
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 channel for free. This issue has been patched in version 0.4.11.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Wevm | Mppx | < 0.4.11 |
Related Weaknesses (CWE)
References
- https://github.com/wevm/mppx/commit/94088246ee18f21b5d6be40d9e7a464f5a280bfbPatch
- https://github.com/wevm/mppx/releases/tag/[email protected]Release Notes
- https://github.com/wevm/mppx/security/advisories/GHSA-mv9j-8jvg-j8mrPatchVendor Advisory
FAQ
What is CVE-2026-34209?
CVE-2026-34209 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 ...
How severe is CVE-2026-34209?
CVE-2026-34209 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-34209?
Check the references section above for vendor advisories and patch information. Affected products include: Wevm Mppx.