What is GHSA-mv9j-8jvg-j8mr?

GHSA-mv9j-8jvg-j8mr is a security advisory published by GitHub Security Advisories with High severity. mppx: Tempo has a session close voucher bypass vulnerability due to settled amount equality

Which CVE IDs does GHSA-mv9j-8jvg-j8mr cover?

GHSA-mv9j-8jvg-j8mr covers the following CVE IDs: CVE-2026-34209. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-mv9j-8jvg-j8mr?

GHSA-mv9j-8jvg-j8mr has a CVSS v3 base score of 7.5, published by GitHub Security Advisories.

Which products are affected by GHSA-mv9j-8jvg-j8mr?

GHSA-mv9j-8jvg-j8mr affects 1 product, including: npm/mppx:\u003c 0.4.11.

GHSA-mv9j-8jvg-j8mrHighCVSS 7.5

mppx: Tempo has a session close voucher bypass vulnerability due to settled amount equality

Vendor

GitHub Security Advisories

Published

March 29, 2026

Last Modified

March 31, 2026

🔗 CVE IDs covered (1)

CVE-2026-34209 →

📋 Description

Impact

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.

Patches

Fixed in 0.4.11.

Workarounds

There are no workarounds available for this vulnerability.

🎯 Affected products1

npm/mppx:< 0.4.11

🔗 References (5)

https://github.com/wevm/mppx/security/advisories/GHSA-mv9j-8jvg-j8mr
https://github.com/wevm/mppx/commit/94088246ee18f21b5d6be40d9e7a464f5a280bfb
https://github.com/wevm/mppx/releases/tag/[email protected]
https://nvd.nist.gov/vuln/detail/CVE-2026-34209
https://github.com/advisories/GHSA-mv9j-8jvg-j8mr