CVE-2026-34209 is a high-severity vulnerability (CVSS 7.5) affecting the mppx TypeScript interface for machine payments protocol, specifically versions prior to 0.4.11. The flaw lies in the tempo/session cooperative close handler, which improperly validates close voucher amounts using "<" instead of "<=" against the on-chain settled amount. This allows an unauthenticated attacker to submit a close voucher exactly equal to the settled amount, effectively closing or griefing a payment channel without committing new funds, impacting integrity. While there is no evidence of active exploitation or public exploit code, the vulnerability has garnered some community discussion on platforms like Bluesky and Mastodon.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 0.4.11CPE matchmatch criteria | cpe:2.3:a:wevm:mppx:*:*:*:*:*:node.js:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.