{"id":"GHSA-mv9j-8jvg-j8mr","summary":"mppx: Tempo has a session close voucher bypass vulnerability due to settled amount equality","details":"### Impact\n\nThe `tempo/session` cooperative close handler validated the close voucher amount using `\u003c` instead of `\u003c=` 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.\n\n### Patches\n\nFixed in 0.4.11.\n\n### Workarounds\n\nThere are no workarounds available for this vulnerability.","aliases":["CVE-2026-34209"],"modified":"2026-03-31T19:05:19.688464Z","published":"2026-03-29T15:10:03Z","database_specific":{"github_reviewed_at":"2026-03-29T15:10:03Z","nvd_published_at":"2026-03-31T15:16:18Z","cwe_ids":["CWE-294"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/wevm/mppx/security/advisories/GHSA-mv9j-8jvg-j8mr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34209"},{"type":"WEB","url":"https://github.com/wevm/mppx/commit/94088246ee18f21b5d6be40d9e7a464f5a280bfb"},{"type":"PACKAGE","url":"https://github.com/wevm/mppx"},{"type":"WEB","url":"https://github.com/wevm/mppx/releases/tag/mppx@0.4.11"}],"affected":[{"package":{"name":"mppx","ecosystem":"npm","purl":"pkg:npm/mppx"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.4.11"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-mv9j-8jvg-j8mr/GHSA-mv9j-8jvg-j8mr.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}