Vulnerability-Lookup

GHSA-4X9M-P82W-8MMP

Vulnerability from github – Published: 2026-07-28 12:31 – Updated: 2026-07-28 12:31

Details

Use of an insecure cryptographic algorithm in the cashless payment system using NFC wristbands from CasfID Servicios Tecnológicos S.L.U. (version used at Resurrection Fest 2025), which employs cards based on MIFARE Classic technology (FM11RF08S). The cryptographic weakness of the authentication algorithm allows an attacker to retrieve access keys using techniques known as Backdoored Nested Attack, read the wristband’s entire contents, and clone its credentials onto a compatible rewritable card. Exploitation of this vulnerability could enable the impersonation of other attendees, the fraudulent use of the balance associated with their wristbands, and financial losses for both the affected users and the event organizers.

Severity

6.8 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-4648"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-326"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-28T12:16:36Z",
    "severity": "MODERATE"
  },
  "details": "Use of an insecure cryptographic algorithm in the cashless payment system using NFC wristbands from CasfID Servicios Tecnol\u00f3gicos S.L.U. (version used at Resurrection Fest 2025), which employs cards based on MIFARE Classic technology (FM11RF08S). The cryptographic weakness of the authentication algorithm allows an attacker to retrieve access keys using techniques known as Backdoored Nested Attack, read the wristband\u2019s entire contents, and clone its credentials onto a compatible rewritable card. Exploitation of this vulnerability could enable the impersonation of other attendees, the fraudulent use of the balance associated with their wristbands, and financial losses for both the affected users and the event organizers.",
  "id": "GHSA-4x9m-p82w-8mmp",
  "modified": "2026-07-28T12:31:21Z",
  "published": "2026-07-28T12:31:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-4648"
    },
    {
      "type": "WEB",
      "url": "https://www.incibe.es/en/incibe-cert/notices/aviso/insufficient-encryption-level-casfid-servicios-tecnologicos-nfc"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/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-2026-4648 (GCVE-0-2026-4648)

Vulnerability from cvelistv5 – Published: 2026-07-28 11:41 – Updated: 2026-07-28 12:04

Title

Insufficient Encryption Level in CasfID Servicios Tecnológicos NFC Wristbands

Summary

Severity

6.8 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-28 12:04 UTC

CWE

CWE-326 - Inadequate Encryption Strength

Assigner

INCIBE INCIBE root

References

1 reference

URL	Tags
https://www.incibe.es/en/incibe-cert/notices/avis…

Impacted products

1 product

Vendor	Product	Version
CasfID Servicios Tecnológicos	NFC Wristbands	Affected: FM11RF08S variant (custom)

Date Public

2026-07-28 11:31

Credits

Luis Miranda Acebedo

Show details on NVD website

JSON

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  "containers": {
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        "metrics": [
          {
            "other": {
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                "id": "CVE-2026-4648",
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                  },
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                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-28T12:04:32.686293Z",
                "version": "2.0.3"
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          "shortName": "CISA-ADP"
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    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
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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.
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.