Vulnerability-Lookup

CVE-2026-82750 (GCVE-0-2026-82750)

Vulnerability from cvelistv5 – Published: 2026-09-06 16:08 – Updated: 2026-09-06 16:08

Title

Unbounded EIP-7702 authorization list in mpp Tempo fee-payer sponsorship inflates gas cost and sponsors account delegation

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.

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

CWE

CWE-1284 - Improper Validation of Specified Quantity in Input

Assigner

EEF mitre root

References

4 references

URL	Tags
https://github.com/ZenHive/mpp/security/advisorie…	vendor-advisoryrelated
https://cna.erlef.org/cves/CVE-2026-82750.html	related
https://osv.dev/vulnerability/EEF-CVE-2026-82750	related
https://github.com/ZenHive/mpp/commit/0482572b47e…	patch

Impacted products

2 products

Vendor	Product	Version	CPE status
ZenHive	mpp	Affected: 0.2.0 , < 0.16.1 (semver) cpe:2.3:a:ZenHive:mpp::::::::
ZenHive	mpp	Affected: d29d54e507918db00a5b65d90136b73166c017d7 , < 0482572b47e1ffe1537ab80ab613d47b92833c2d (git) cpe:2.3:a:ZenHive:mpp::::::::

Credits

Kian Kai Ang Kian Kai Ang E.FU Jonatan Männchen / EEF

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "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"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eOnly deployments that enable Tempo server-side fee sponsorship are affected, through \u003ccode\u003e\"fee_payer\" =\u0026gt; true\u003c/code\u003e in \u003ccode\u003emethod_config\u003c/code\u003e with either local co-signing (\u003ccode\u003efee_payer_private_key\u003c/code\u003e) or hosted sponsorship (\u003ccode\u003efee_payer_url\u003c/code\u003e). Sponsorship is disabled by default.\u003c/p\u003e"
            },
            {
              "base64": false,
              "type": "text/markdown",
              "value": "Only deployments that enable Tempo server-side fee sponsorship are affected, through `\"fee_payer\" =\u003e true` in `method_config` with either local co-signing (`fee_payer_private_key`) or hosted sponsorship (`fee_payer_url`). Sponsorship is disabled by default."
            }
          ],
          "value": "Only deployments that enable Tempo server-side fee sponsorship are affected, through \"fee_payer\" =\u003e true in method_config with either local co-signing (fee_payer_private_key) or hosted sponsorship (fee_payer_url). Sponsorship is disabled by default."
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "0.16.1",
                  "versionStartIncluding": "0.2.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ],
          "operator": "AND"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Kian Kai Ang"
        },
        {
          "lang": "en",
          "type": "reporter",
          "value": "Kian Kai Ang"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "E.FU"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "Jonatan M\u00e4nnchen / EEF"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eImproper 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.\u003c/p\u003e\n\u003cp\u003eWhen the server sponsors Tempo payments, \u003ccode\u003eMPP.Methods.Tempo.FeePayerPolicy.measure/3\u003c/code\u003e in \u003ccode\u003elib/mpp/methods/tempo/fee_payer_policy.ex\u003c/code\u003e bounds the gas fields, the fee budget, the validity window and the access list of the client-signed \u003ccode\u003e0x76\u003c/code\u003e envelope, but never reads its \u003ccode\u003eaa_authorization_list\u003c/code\u003e 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 \u003ccode\u003egas_limit\u003c/code\u003e 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.\u003c/p\u003e\n\u003cp\u003eThis issue affects mpp: from 0.2.0 before 0.16.1.\u003c/p\u003e"
            },
            {
              "base64": false,
              "type": "text/markdown",
              "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."
            }
          ],
          "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."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-130",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-130 Excessive Allocation"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 8.3,
            "baseSeverity": "HIGH",
            "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-1284",
              "description": "CWE-1284 Improper Validation of Specified Quantity in Input",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-06T16:08:41.089Z",
        "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "shortName": "EEF"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory",
            "related"
          ],
          "url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-5qrp-r24c-w6jr"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://cna.erlef.org/cves/CVE-2026-82750.html"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://osv.dev/vulnerability/EEF-CVE-2026-82750"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/ZenHive/mpp/commit/0482572b47e1ffe1537ab80ab613d47b92833c2d"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Unbounded EIP-7702 authorization list in mpp Tempo fee-payer sponsorship inflates gas cost and sponsors account delegation",
      "workarounds": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eDisable Tempo fee sponsorship by leaving \u003ccode\u003e\"fee_payer\"\u003c/code\u003e at its default of \u003ccode\u003efalse\u003c/code\u003e and setting no \u003ccode\u003efee_payer_url\u003c/code\u003e, so the client pays its own gas. Where sponsorship must stay enabled, lower the \u003ccode\u003emax_gas\u003c/code\u003e override in \u003ccode\u003efee_payer_policy\u003c/code\u003e to just above what a legitimate sponsored payment needs (a TIP-20 transfer is roughly 50,000 gas), so an envelope padded with delegations either fails the policy or runs out of gas at a bounded cost. This bounds the inflation without closing it.\u003c/p\u003e"
            },
            {
              "base64": false,
              "type": "text/markdown",
              "value": "Disable Tempo fee sponsorship by leaving `\"fee_payer\"` at its default of `false` and setting no `fee_payer_url`, so the client pays its own gas. Where sponsorship must stay enabled, lower the `max_gas` override in `fee_payer_policy` to just above what a legitimate sponsored payment needs (a TIP-20 transfer is roughly 50,000 gas), so an envelope padded with delegations either fails the policy or runs out of gas at a bounded cost. This bounds the inflation without closing it."
            }
          ],
          "value": "Disable Tempo fee sponsorship by leaving \"fee_payer\" at its default of false and setting no fee_payer_url, so the client pays its own gas. Where sponsorship must stay enabled, lower the max_gas override in fee_payer_policy to just above what a legitimate sponsored payment needs (a TIP-20 transfer is roughly 50,000 gas), so an envelope padded with delegations either fails the policy or runs out of gas at a bounded cost. This bounds the inflation without closing it."
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
    "assignerShortName": "EEF",
    "cveId": "CVE-2026-82750",
    "datePublished": "2026-09-06T16:08:41.089Z",
    "dateReserved": "2026-08-31T01:00:09.774Z",
    "dateUpdated": "2026-09-06T16:08:41.089Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-82750",
      "date": "2026-09-07",
      "epss": "0.00329",
      "percentile": "0.25623"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-82750\",\"sourceIdentifier\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"published\":\"2026-09-06T17:17:55.867\",\"lastModified\":\"2026-09-06T17:17:55.867\",\"vulnStatus\":\"Received\",\"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.\"}],\"affected\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"affectedData\":[{\"vendor\":\"ZenHive\",\"product\":\"mpp\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://repo.hex.pm\",\"packageName\":\"mpp\",\"cpes\":[\"cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*\"],\"modules\":[\"\u0027Elixir.MPP.Methods.Tempo.FeePayerPolicy\u0027\",\"\u0027Elixir.MPP.Methods.Tempo\u0027\"],\"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\",\"packageURL\":\"pkg:hex/mpp\",\"versions\":[{\"version\":\"0.2.0\",\"lessThan\":\"0.16.1\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"ZenHive\",\"product\":\"mpp\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://github.com\",\"packageName\":\"zenhive/mpp\",\"cpes\":[\"cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*\"],\"modules\":[\"\u0027Elixir.MPP.Methods.Tempo.FeePayerPolicy\u0027\",\"\u0027Elixir.MPP.Methods.Tempo\u0027\"],\"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\",\"packageURL\":\"pkg:github/zenhive/mpp\",\"versions\":[{\"version\":\"d29d54e507918db00a5b65d90136b73166c017d7\",\"lessThan\":\"0482572b47e1ffe1537ab80ab613d47b92833c2d\",\"versionType\":\"git\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"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\",\"baseScore\":8.3,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"HIGH\",\"vulnAvailabilityImpact\":\"LOW\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}]},\"weaknesses\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-1284\"}]}],\"references\":[{\"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\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"}]}}"
  }
}

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

References

	URL	Tags
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://cna.erlef.org/cves/CVE-2026-82750.html
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://github.com/ZenHive/mpp/commit/0482572b47e1ffe1537ab80ab613d47b92833c2d
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://github.com/ZenHive/mpp/security/advisories/GHSA-5qrp-r24c-w6jr
	6b3ad84c-e1a6-4bf7-a703-f496b71e49db	https://osv.dev/vulnerability/EEF-CVE-2026-82750

Impacted products

	Vendor	Product	Version

JSON

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"
    }
  ]
}

GHSA-Q4F3-JF9F-788F

Vulnerability from github – Published: 2026-09-06 18:34 – Updated: 2026-09-06 18:34

Details

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.

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

Show details on source website

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To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-82750"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1284"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-06T17:17:55Z",
    "severity": "HIGH"
  },
  "details": "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": "GHSA-q4f3-jf9f-788f",
  "modified": "2026-09-06T18:34:38Z",
  "published": "2026-09-06T18:34:38Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-5qrp-r24c-w6jr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-82750"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ZenHive/mpp/commit/0482572b47e1ffe1537ab80ab613d47b92833c2d"
    },
    {
      "type": "WEB",
      "url": "https://cna.erlef.org/cves/CVE-2026-82750.html"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-82750"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ]
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

CVE-2026-82750 (GCVE-0-2026-82750)

FKIE_CVE-2026-82750

GHSA-Q4F3-JF9F-788F

Tags

Sightings

Nomenclature