CVE-2026-89420Public exploitNetwork attack vectorHinoki check available

Unpaid resource access via reusable zero-delta voucher

Published Sep 22, 2026 · Updated Sep 22, 2026

Payment bypass in ZenHive MPP 0.14.0 through 0.16.1 allows remote attackers with an open channel to obtain paid resources without charges. MPP.Session.Actions.accept_voucher/3 accepts a voucher equal to the channel's recorded cumulative amount without invoking maybe_spend/2. A valid open channel and signed voucher are required; replaying that voucher under fresh challenges yields unlimited units while spending remains unchanged.

CVSS severity7.5
High
EPSS probability0.41%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Payment bypass in ZenHive MPP 0.14.0 through 0.16.1 allows remote attackers with an open channel to obtain paid resources without charges. MPP.Session.Actions.accept_voucher/3 accepts a voucher equal to the channel's recorded cumulative amount without invoking maybe_spend/2. A valid open channel and signed voucher are required; replaying that voucher under fresh challenges yields unlimited units while spending remains unchanged.

The record

CVE
CVE-2026-89420
Published
Sep 22, 2026
Updated
Sep 22, 2026
Vendor
ZenHive
Product
MPP
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 22, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.14.0 <0.16.2
  2. Affected versionversion=82df569c898be1137189e3648e1edb4af6363651 <7270edc1dcfb58250cc5ee812876609206564165

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ZenHive · MPPversion=0.14.0 <0.16.2; version=82df569c898be1137189e3648e1edb4af6363651 <7270edc1dcfb58250cc5ee812876609206564165

Published CVSS scores

7.5GitHub Security AdvisoryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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