{"cve":"CVE-2026-59695","nvd":{"published":"2026-07-17T11:17:14.117","modified":"2026-10-24T20:10:00.137","status":"Deferred","description":"Improper Validation of Specified Quantity in Input in ZenHive mpp allows an unauthenticated remote client to drain the fee-payer wallet in a single request by naming an arbitrarily high gas price.\n\nWhen the mpp Elixir library is configured as fee payer (fee_payer: true), MPP.Tempo.Transaction.cosign_fee_payer/3 re-signs the client-supplied base fields of the 0x76 AASigned envelope verbatim, including max_fee_per_gas and max_priority_fee_per_gas, without validating that they are within reasonable bounds. A malicious client embeds arbitrarily large values for these fields in the signed envelope. The server co-signs and broadcasts the transaction. The effective_gas_price billed against the fee-payer wallet is derived from the attacker-supplied ceilings, so the server pays those inflated per-gas rates out of its own wallet. A single crafted request can drain the wallet entirely, after which the server can no longer sponsor gas for legitimate payment requests.\n\nThis issue affects mpp: from 0.2.0 before 0.6.0.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N","score":8.3},"cvss_v3":null,"cwes":["CWE-1284"],"references":["https://cna.erlef.org/cves/CVE-2026-59695.html","https://github.com/ZenHive/mpp/commit/5d6338e2334084c5f2a78cfcca474830733ed7e8","https://github.com/ZenHive/mpp/security/advisories/GHSA-vv77-66rf-pm86","https://osv.dev/vulnerability/EEF-CVE-2026-59695","https://github.com/ZenHive/mpp/security/advisories/GHSA-vv77-66rf-pm86"],"products":[],"source":"nvd","synced_at":"2026-10-25T17:50:08.599881581+00:00"},"epss":{"cve":"CVE-2026-59695","score":0.00524,"percentile":0.44135,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}