Vulnerability-Lookup

GHSA-R4HX-MHRP-XF73

Vulnerability from github – Published: 2026-07-17 12:31 – Updated: 2026-07-17 12:31

Details

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 the EIP-2930 access list, without validating its length or contents. EIP-2930 access list entries incur intrinsic gas (~2,400 gas per address, plus 1,900 gas per storage key) charged before any opcode executes, regardless of whether the listed addresses are ever touched. A malicious client submits a valid transferWithMemo call alongside a large number of fabricated access-list entries. The server co-signs and broadcasts the transaction. The intended transfer executes normally, but the fee-payer wallet pays a large multiple of the expected gas cost with no corresponding on-chain work.

At the maintainer's default of 137 access-list entries (fitting within Bandit's 10,000-byte per-header-field limit) and 100 Gwei max_fee_per_gas, per-payment gas cost rises from ~51,287 to ~380,087 gas, a 7.4x multiplier. Sustained abuse destroys the sponsor's operating margin on low-cost payments and, over time, drains the fee-payer wallet.

This issue affects mpp: from 0.2.0 before 0.6.0.

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

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-59694"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1284"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-17T11:17:13Z",
    "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 payment by a large multiplier, degrading the sponsor\u0027s operating margin.\n\nWhen 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 the EIP-2930 access list, without validating its length or contents. EIP-2930 access list entries incur intrinsic gas (~2,400 gas per address, plus 1,900 gas per storage key) charged before any opcode executes, regardless of whether the listed addresses are ever touched. A malicious client submits a valid transferWithMemo call alongside a large number of fabricated access-list entries. The server co-signs and broadcasts the transaction. The intended transfer executes normally, but the fee-payer wallet pays a large multiple of the expected gas cost with no corresponding on-chain work.\n\nAt the maintainer\u0027s default of 137 access-list entries (fitting within Bandit\u0027s 10,000-byte per-header-field limit) and 100 Gwei max_fee_per_gas, per-payment gas cost rises from ~51,287 to ~380,087 gas, a 7.4x multiplier. Sustained abuse destroys the sponsor\u0027s operating margin on low-cost payments and, over time, drains the fee-payer wallet.\n\nThis issue affects mpp: from 0.2.0 before 0.6.0.",
  "id": "GHSA-r4hx-mhrp-xf73",
  "modified": "2026-07-17T12:31:29Z",
  "published": "2026-07-17T12:31:29Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-qpxh-ff8m-c62v"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59694"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ZenHive/mpp/commit/5d6338e2334084c5f2a78cfcca474830733ed7e8"
    },
    {
      "type": "WEB",
      "url": "https://cna.erlef.org/cves/CVE-2026-59694.html"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-59694"
    }
  ],
  "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"
    }
  ]
}

CVE-2026-59694 (GCVE-0-2026-59694)

Vulnerability from cvelistv5 – Published: 2026-07-17 10:11 – Updated: 2026-07-18 04:12

Title

Unbounded access list in mpp Tempo fee-payer inflates gas cost per payment

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 payment by a large multiplier, degrading the sponsor's operating margin. 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 the EIP-2930 access list, without validating its length or contents. EIP-2930 access list entries incur intrinsic gas (~2,400 gas per address, plus 1,900 gas per storage key) charged before any opcode executes, regardless of whether the listed addresses are ever touched. A malicious client submits a valid transferWithMemo call alongside a large number of fabricated access-list entries. The server co-signs and broadcasts the transaction. The intended transfer executes normally, but the fee-payer wallet pays a large multiple of the expected gas cost with no corresponding on-chain work. At the maintainer's default of 137 access-list entries (fitting within Bandit's 10,000-byte per-header-field limit) and 100 Gwei max_fee_per_gas, per-payment gas cost rises from ~51,287 to ~380,087 gas, a 7.4x multiplier. Sustained abuse destroys the sponsor's operating margin on low-cost payments and, over time, drains the fee-payer wallet. This issue affects mpp: from 0.2.0 before 0.6.0.

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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-17 12:22 UTC

CWE

CWE-1284 - Improper Validation of Specified Quantity in Input

Assigner

EEF CNA under the mitre root

CNA scorecard A 96/100 over 297 records in the last 180 days details

References

4 references

URL	Tags
https://github.com/ZenHive/mpp/security/advisorie…	vendor-advisoryrelated
https://cna.erlef.org/cves/CVE-2026-59694.html	related
https://osv.dev/vulnerability/EEF-CVE-2026-59694	related
https://github.com/ZenHive/mpp/commit/5d6338e2334…	patch

Impacted products

2 products

Vendor	Product	Version
ZenHive	mpp	Affected: 0.2.0 , < 0.6.0 (semver) cpe:2.3:a:ZenHive:mpp::::::::
ZenHive	mpp	Affected: d29d54e507918db00a5b65d90136b73166c017d7 , < 5d6338e2334084c5f2a78cfcca474830733ed7e8 (git) cpe:2.3:a:ZenHive:mpp::::::::

Credits

Kian Kai Ang E.FU Jonatan Männchen / EEF

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-59694",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-17T12:22:40.105353Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-17T12:22:45.224Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-qpxh-ff8m-c62v"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://repo.hex.pm",
          "cpes": [
            "cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "\u0027Elixir.MPP.Tempo.Transaction\u0027"
          ],
          "packageName": "mpp",
          "packageURL": "pkg:hex/mpp",
          "product": "mpp",
          "programFiles": [
            "lib/mpp/tempo/transaction.ex"
          ],
          "programRoutines": [
            {
              "name": "\u0027Elixir.MPP.Tempo.Transaction\u0027:cosign_fee_payer/3"
            }
          ],
          "repo": "https://github.com/ZenHive/mpp",
          "vendor": "ZenHive",
          "versions": [
            {
              "lessThan": "0.6.0",
              "status": "affected",
              "version": "0.2.0",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://github.com",
          "cpes": [
            "cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unaffected",
          "modules": [
            "\u0027Elixir.MPP.Tempo.Transaction\u0027"
          ],
          "packageName": "ZenHive/mpp",
          "packageURL": "pkg:github/ZenHive/mpp",
          "product": "mpp",
          "programFiles": [
            "lib/mpp/tempo/transaction.ex"
          ],
          "programRoutines": [
            {
              "name": "\u0027Elixir.MPP.Tempo.Transaction\u0027:cosign_fee_payer/3"
            }
          ],
          "repo": "https://github.com/ZenHive/mpp",
          "vendor": "ZenHive",
          "versions": [
            {
              "lessThan": "5d6338e2334084c5f2a78cfcca474830733ed7e8",
              "status": "affected",
              "version": "d29d54e507918db00a5b65d90136b73166c017d7",
              "versionType": "git"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eThe vulnerable code path is only reachable when the \u003ctt\u003eMPP.Methods.Tempo\u003c/tt\u003e method is configured with \u003ctt\u003efee_payer: true\u003c/tt\u003e (server-side gas sponsorship). Default deployments with \u003ctt\u003efee_payer: false\u003c/tt\u003e are not affected, since the client pays for gas out of its own wallet.\u003c/p\u003e"
            }
          ],
          "value": "The vulnerable code path is only reachable when the MPP.Methods.Tempo method is configured with fee_payer: true (server-side gas sponsorship). Default deployments with fee_payer: false are not affected, since the client pays for gas out of its own wallet."
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "0.6.0",
                  "versionStartIncluding": "0.2.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "AND"
            }
          ],
          "operator": "OR"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Kian Kai Ang"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "E.FU"
        },
        {
          "lang": "en",
          "type": "analyst",
          "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 payment by a large multiplier, degrading the sponsor\u0027s operating margin.\u003c/p\u003e\u003cp\u003eWhen the \u003ctt\u003empp\u003c/tt\u003e Elixir library is configured as fee payer (\u003ctt\u003efee_payer: true\u003c/tt\u003e), \u003ctt\u003eMPP.Tempo.Transaction.cosign_fee_payer/3\u003c/tt\u003e re-signs the client-supplied base fields of the \u003ctt\u003e0x76\u003c/tt\u003e AASigned envelope verbatim, including the EIP-2930 access list, without validating its length or contents. EIP-2930 access list entries incur intrinsic gas (~2,400 gas per address, plus 1,900 gas per storage key) charged before any opcode executes, regardless of whether the listed addresses are ever touched. A malicious client submits a valid \u003ctt\u003etransferWithMemo\u003c/tt\u003e call alongside a large number of fabricated access-list entries. The server co-signs and broadcasts the transaction. The intended transfer executes normally, but the fee-payer wallet pays a large multiple of the expected gas cost with no corresponding on-chain work.\u003c/p\u003e\u003cp\u003eAt the maintainer\u0027s default of 137 access-list entries (fitting within Bandit\u0027s 10,000-byte per-header-field limit) and 100 Gwei \u003ctt\u003emax_fee_per_gas\u003c/tt\u003e, per-payment gas cost rises from ~51,287 to ~380,087 gas, a 7.4x multiplier. Sustained abuse destroys the sponsor\u0027s operating margin on low-cost payments and, over time, drains the fee-payer wallet.\u003c/p\u003e\u003cp\u003eThis issue affects mpp: from 0.2.0 before 0.6.0.\u003c/p\u003e"
            }
          ],
          "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 payment by a large multiplier, degrading the sponsor\u0027s operating margin.\n\nWhen 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 the EIP-2930 access list, without validating its length or contents. EIP-2930 access list entries incur intrinsic gas (~2,400 gas per address, plus 1,900 gas per storage key) charged before any opcode executes, regardless of whether the listed addresses are ever touched. A malicious client submits a valid transferWithMemo call alongside a large number of fabricated access-list entries. The server co-signs and broadcasts the transaction. The intended transfer executes normally, but the fee-payer wallet pays a large multiple of the expected gas cost with no corresponding on-chain work.\n\nAt the maintainer\u0027s default of 137 access-list entries (fitting within Bandit\u0027s 10,000-byte per-header-field limit) and 100 Gwei max_fee_per_gas, per-payment gas cost rises from ~51,287 to ~380,087 gas, a 7.4x multiplier. Sustained abuse destroys the sponsor\u0027s operating margin on low-cost payments and, over time, drains the fee-payer wallet.\n\nThis issue affects mpp: from 0.2.0 before 0.6.0."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-130",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-130 Excessive Allocation"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 8.3,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "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"
          },
          "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": "2026-07-18T04:12:36.335Z",
        "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
        "shortName": "EEF"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory",
            "related"
          ],
          "url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-qpxh-ff8m-c62v"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://cna.erlef.org/cves/CVE-2026-59694.html"
        },
        {
          "tags": [
            "related"
          ],
          "url": "https://osv.dev/vulnerability/EEF-CVE-2026-59694"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/ZenHive/mpp/commit/5d6338e2334084c5f2a78cfcca474830733ed7e8"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Unbounded access list in mpp Tempo fee-payer inflates gas cost per payment",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db",
    "assignerShortName": "EEF",
    "cveId": "CVE-2026-59694",
    "datePublished": "2026-07-17T10:11:49.192Z",
    "dateReserved": "2026-07-06T14:05:47.003Z",
    "dateUpdated": "2026-07-18T04:12:36.335Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

GHSA-R4HX-MHRP-XF73

CVE-2026-59694 (GCVE-0-2026-59694)

Tags

Sightings

Nomenclature

Related by attack behaviour