EEF-CVE-2026-67581

Source
https://cna.erlef.org/osv/EEF-CVE-2026-67581.html
Import Source
https://cna.erlef.org/osv/EEF-CVE-2026-67581.json
JSON Data
https://api.osv.dev/v1/vulns/EEF-CVE-2026-67581
Aliases
Published
2026-08-19T17:20:09.606Z
Modified
2026-08-19T17:42:02.999886944Z
Severity
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
On-chain transfer proof is not single-use in mpp EVM payment method, enabling cross-challenge replay
Details

Summary

Authentication Bypass by Capture-replay in ZenHive mpp allows an unauthenticated remote client to obtain paid resources by resubmitting one settled on-chain transfer.

MPP.Methods.EVM.verify/2 accepts a transaction-hash credential and matches a transfer purely on token, to and amount (ERC-20) or to and value (native). It binds the proof neither to the challenge being verified nor to any record of prior use, and the generic MPP.Plug dedup store keys on challenge.id, which is regenerated for every 402 response. On a static-price route, a single historical transfer matching the charge therefore satisfies an unbounded number of later charges, including transfers an attacker can read off a public block explorer.

This issue affects mpp: from 0.3.0 before 0.6.3.

Workaround

Price each challenge uniquely (per-challenge or single-use amounts) so that a historical transfer cannot match a later charge, and keep challenge expiry short to narrow the window in which any given transfer stays useful. Deployments that can use the Tempo method for on-chain payments get per-challenge attribution binding instead.

Database specific
{
    "capec_ids": [
        "CAPEC-60"
    ],
    "cwe_ids": [
        "CWE-294"
    ],
    "cpe_ids": [
        "cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*"
    ]
}
References
Credits
    • E.FU - FINDER
    • E.FU - REMEDIATION_DEVELOPER
    • Jonatan Männchen / EEF - ANALYST

Affected packages

Hex / mpp

Package

Name
mpp
Purl
pkg:hex/mpp

Affected ranges

Type
SEMVER
Events
Introduced
0.3.0
Fixed
0.6.3

Affected versions

0.*
0.3.0
0.3.1
0.3.2
0.4.0
0.6.0
0.6.1
0.6.2

Database specific

source
"https://cna.erlef.org/osv/EEF-CVE-2026-67581.json"

Git / github.com/ZenHive/mpp

Affected ranges

Type
GIT
Repo
https://github.com/ZenHive/mpp
Events

Affected versions

v0.*
v0.3.0
v0.4.0
v0.5.1
v0.6.0
v0.6.1

Database specific

source
"https://cna.erlef.org/osv/EEF-CVE-2026-67581.json"