Vulnerability-Lookup

GHSA-CW4V-5GCF-X3CW

Vulnerability from github – Published: 2026-08-19 18:32 – Updated: 2026-08-19 18:32

Details

Authentication Bypass by Capture-replay in ZenHive mpp allows an unauthenticated third party to obtain paid resources by replaying a transfer settled by an unrelated payer.

MPP.Methods.Tempo normally binds a settled TIP-20 TransferWithMemo to the specific challenge under verification through an attribution nonce carried in the memo. When a static "memo" is configured in method_config, check_matched_memo_binding/3 returns the match unconditionally and that binding is skipped, leaving only token, recipient, amount and the static memo value to match on. The static memo is echoed in every unauthenticated 402 response and Tempo transfers are public, so an attacker can take any matching transfer paid by a legitimate customer, request a fresh challenge for the same route, and present that transaction hash as a type="hash" credential. The hash path performs no sender or signature check tying the presenter to the wallet that broadcast the transfer.

This issue affects mpp: from 0.6.1 before 0.6.4.

Severity

8.2 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-73136"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-294"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-19T18:17:25Z",
    "severity": "HIGH"
  },
  "details": "Authentication Bypass by Capture-replay in ZenHive mpp allows an unauthenticated third party to obtain paid resources by replaying a transfer settled by an unrelated payer.\n\nMPP.Methods.Tempo normally binds a settled TIP-20 TransferWithMemo to the specific challenge under verification through an attribution nonce carried in the memo. When a static \"memo\" is configured in method_config, check_matched_memo_binding/3 returns the match unconditionally and that binding is skipped, leaving only token, recipient, amount and the static memo value to match on. The static memo is echoed in every unauthenticated 402 response and Tempo transfers are public, so an attacker can take any matching transfer paid by a legitimate customer, request a fresh challenge for the same route, and present that transaction hash as a type=\"hash\" credential. The hash path performs no sender or signature check tying the presenter to the wallet that broadcast the transfer.\n\nThis issue affects mpp: from 0.6.1 before 0.6.4.",
  "id": "GHSA-cw4v-5gcf-x3cw",
  "modified": "2026-08-19T18:32:54Z",
  "published": "2026-08-19T18:32:54Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-34g7-vx6g-82mq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-73136"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ZenHive/mpp/commit/2207d7f456ae14c1d3fcacc6f635bf4f8cee1a34"
    },
    {
      "type": "WEB",
      "url": "https://cna.erlef.org/cves/CVE-2026-73136.html"
    },
    {
      "type": "WEB",
      "url": "https://osv.dev/vulnerability/EEF-CVE-2026-73136"
    }
  ],
  "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:N/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-2026-73136 (GCVE-0-2026-73136)

Vulnerability from cvelistv5 – Published: 2026-08-19 17:19 – Updated: 2026-08-19 18:54

Title

Static memo configuration in mpp Tempo disables per-challenge attribution binding, enabling third-party replay

Summary

Authentication Bypass by Capture-replay in ZenHive mpp allows an unauthenticated third party to obtain paid resources by replaying a transfer settled by an unrelated payer. MPP.Methods.Tempo normally binds a settled TIP-20 TransferWithMemo to the specific challenge under verification through an attribution nonce carried in the memo. When a static "memo" is configured in method_config, check_matched_memo_binding/3 returns the match unconditionally and that binding is skipped, leaving only token, recipient, amount and the static memo value to match on. The static memo is echoed in every unauthenticated 402 response and Tempo transfers are public, so an attacker can take any matching transfer paid by a legitimate customer, request a fresh challenge for the same route, and present that transaction hash as a type="hash" credential. The hash path performs no sender or signature check tying the presenter to the wallet that broadcast the transfer. This issue affects mpp: from 0.6.1 before 0.6.4.

Severity

8.2 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-19 18:49 UTC

CWE

CWE-294 - Authentication Bypass by Capture-replay

Assigner

EEF mitre root

References

4 references

URL	Tags
https://github.com/ZenHive/mpp/security/advisorie…	vendor-advisoryrelated
https://cna.erlef.org/cves/CVE-2026-73136.html	related
https://osv.dev/vulnerability/EEF-CVE-2026-73136	related
https://github.com/ZenHive/mpp/commit/2207d7f456a…	patch

Impacted products

2 products

Vendor	Product	Version
ZenHive	mpp	Affected: 0.6.1 , < 0.6.4 (semver) cpe:2.3:a:ZenHive:mpp::::::::
ZenHive	mpp	Affected: 542a525563c2fcedd670b593437deca81c6797a4 , < 2207d7f456ae14c1d3fcacc6f635bf4f8cee1a34 (git) cpe:2.3:a:ZenHive:mpp::::::::

Date Public

2026-07-06 00:00

Credits

E.FU E.FU Jonatan Männchen / EEF

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JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
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                "id": "CVE-2026-73136",
                "options": [
                  {
                    "Exploitation": "none"
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                  {
                    "Technical Impact": "partial"
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                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-19T18:49:35.273666Z",
                "version": "2.0.3"
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
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            "cpe:2.3:a:ZenHive:mpp:*:*:*:*:*:*:*:*"
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          "defaultStatus": "unaffected",
          "modules": [
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              "name": "\u0027Elixir.MPP.Methods.Tempo\u0027:verify/2"
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      "configurations": [
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          ],
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            },
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              "base64": false,
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      "title": "Static memo configuration in mpp Tempo disables per-challenge attribution binding, enabling third-party replay",
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}

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

GHSA-CW4V-5GCF-X3CW

CVE-2026-73136 (GCVE-0-2026-73136)

Tags

Sightings

Nomenclature