---
cve: "CVE-2026-59695"
severity: "HIGH"
cvss: 8.3
epss: "30%"
vendor: "ZenHive"
kev: false
exploited: false
published: "2026-07-17 11:17:14"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-19T19:05:37+02:00"
---

# CVE-2026-59695

> 8.3 HIGH · 🧪 PoC

## Beschreibung

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.

When 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.

This issue affects mpp: from 0.2.0 before 0.6.0.

## CVSS-Vektor

```
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
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 422bcdd066d1457a93bf5e75fd55e71c5e0be961 (Commit)
- 5d6338e2334084c5f2a78cfcca474830733ed7e8 (Commit)

## Referenzen

- <https://github.com/ZenHive/mpp/security/advisories/GHSA-vv77-66rf-pm86>
- <https://cna.erlef.org/cves/CVE-2026-59695.html>
- <https://osv.dev/vulnerability/EEF-CVE-2026-59695>
- <https://github.com/ZenHive/mpp/commit/5d6338e2334084c5f2a78cfcca474830733ed7e8>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-59695) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_