GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

FKIE_CVE-2026-82750

Vulnerability from fkie_nvd - Published: 2026-09-06 17:17 - Updated: 2026-09-06 17:17
Severity
8.3 (High) - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N
Summary
Improper Validation of Specified Quantity in Input in ZenHive mpp allows an unauthenticated remote client to inflate the fee-payer's gas cost per sponsored payment by a large multiplier and to have the sponsor pay for EIP-7702 account delegations of the client's choosing. When the server sponsors Tempo payments, MPP.Methods.Tempo.FeePayerPolicy.measure/3 in lib/mpp/methods/tempo/fee_payer_policy.ex bounds the gas fields, the fee budget, the validity window and the access list of the client-signed 0x76 envelope, but never reads its aa_authorization_list field. Every signed delegation in that list is charged as intrinsic gas before the payment call runs, so a client attaching delegations from throwaway authority keys makes the sponsor pay for them within the default gas_limit ceiling. At the reporter's default of seven entries the sponsored cost rises from about 46,575 gas to about 1,884,087 gas. Because each entry is applied as a persistent set-code delegation, a client can also upgrade its own accounts to delegated code at the sponsor's expense. This issue affects mpp: from 0.2.0 before 0.16.1.
References
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://cna.erlef.org/cves/CVE-2026-82750.html
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://github.com/ZenHive/mpp/commit/0482572b47e1ffe1537ab80ab613d47b92833c2d
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://github.com/ZenHive/mpp/security/advisories/GHSA-5qrp-r24c-w6jr
6b3ad84c-e1a6-4bf7-a703-f496b71e49dbhttps://osv.dev/vulnerability/EEF-CVE-2026-82750
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://repo.hex.pm",
          "cpes": [
            "cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "\u0027Elixir.MPP.Methods.Tempo.FeePayerPolicy\u0027",
            "\u0027Elixir.MPP.Methods.Tempo\u0027"
          ],
          "packageName": "mpp",
          "packageURL": "pkg:hex/mpp",
          "product": "mpp",
          "programFiles": [
            "lib/mpp/methods/tempo/fee_payer_policy.ex",
            "lib/mpp/methods/tempo.ex"
          ],
          "programRoutines": [
            {
              "name": "\u0027Elixir.MPP.Methods.Tempo.FeePayerPolicy\u0027:measure/3"
            },
            {
              "name": "\u0027Elixir.MPP.Methods.Tempo.FeePayerPolicy\u0027:validate/3"
            },
            {
              "name": "\u0027Elixir.MPP.Methods.Tempo\u0027:verify/2"
            }
          ],
          "repo": "https://github.com/ZenHive/mpp",
          "vendor": "ZenHive",
          "versions": [
            {
              "lessThan": "0.16.1",
              "status": "affected",
              "version": "0.2.0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://github.com",
          "cpes": [
            "cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "\u0027Elixir.MPP.Methods.Tempo.FeePayerPolicy\u0027",
            "\u0027Elixir.MPP.Methods.Tempo\u0027"
          ],
          "packageName": "zenhive/mpp",
          "packageURL": "pkg:github/zenhive/mpp",
          "product": "mpp",
          "programFiles": [
            "lib/mpp/methods/tempo/fee_payer_policy.ex",
            "lib/mpp/methods/tempo.ex"
          ],
          "programRoutines": [
            {
              "name": "\u0027Elixir.MPP.Methods.Tempo.FeePayerPolicy\u0027:measure/3"
            },
            {
              "name": "\u0027Elixir.MPP.Methods.Tempo.FeePayerPolicy\u0027:validate/3"
            },
            {
              "name": "\u0027Elixir.MPP.Methods.Tempo\u0027:verify/2"
            }
          ],
          "repo": "https://github.com/ZenHive/mpp",
          "vendor": "ZenHive",
          "versions": [
            {
              "lessThan": "0482572b47e1ffe1537ab80ab613d47b92833c2d",
              "status": "affected",
              "version": "d29d54e507918db00a5b65d90136b73166c017d7",
              "versionType": "git"
            }
          ]
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Improper Validation of Specified Quantity in Input in ZenHive mpp allows an unauthenticated remote client to inflate the fee-payer\u0027s gas cost per sponsored payment by a large multiplier and to have the sponsor pay for EIP-7702 account delegations of the client\u0027s choosing.\n\nWhen the server sponsors Tempo payments, MPP.Methods.Tempo.FeePayerPolicy.measure/3 in lib/mpp/methods/tempo/fee_payer_policy.ex bounds the gas fields, the fee budget, the validity window and the access list of the client-signed 0x76 envelope, but never reads its aa_authorization_list field. Every signed delegation in that list is charged as intrinsic gas before the payment call runs, so a client attaching delegations from throwaway authority keys makes the sponsor pay for them within the default gas_limit ceiling. At the reporter\u0027s default of seven entries the sponsored cost rises from about 46,575 gas to about 1,884,087 gas. Because each entry is applied as a persistent set-code delegation, a client can also upgrade its own accounts to delegated code at the sponsor\u0027s expense.\n\nThis issue affects mpp: from 0.2.0 before 0.16.1."
    }
  ],
  "id": "CVE-2026-82750",
  "lastModified": "2026-09-06T17:17:55.867",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 8.3,
          "baseSeverity": "HIGH",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "LOW",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "HIGH",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-09-06T17:17:55.867",
  "references": [
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://cna.erlef.org/cves/CVE-2026-82750.html"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/ZenHive/mpp/commit/0482572b47e1ffe1537ab80ab613d47b92833c2d"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-5qrp-r24c-w6jr"
    },
    {
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-82750"
    }
  ],
  "sourceIdentifier": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1284"
        }
      ],
      "source": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
      "type": "Secondary"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.