6.8
MEDIUM CVSS 4.0
CVE-2026-4648
Insufficient Encryption Level in CasfID Servicios Tecnológicos NFC Wristbands
Description

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.

INFO

Published Date :

July 28, 2026, 12:16 p.m.

Last Modified :

July 28, 2026, 1:18 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-4648 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 4.0 MEDIUM 0cbda920-cd7f-484a-8e76-bf7f4b7f4516
CVSS 4.0 MEDIUM [email protected]
Solution
Update cryptographic algorithms and authentication methods to secure payment system.
  • Migrate from MIFARE Classic to a secure contactless technology.
  • Implement stronger cryptographic algorithms for authentication.
  • Update NFC wristband firmware to enforce new security standards.
  • Consider tokenization for payment data.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-4648.

URL Resource
https://www.incibe.es/en/incibe-cert/notices/aviso/insufficient-encryption-level-casfid-servicios-tecnologicos-nfc
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-4648 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-4648 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-4648 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-4648 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 28, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-4648', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-07-28T12:04:32.686293Z'}
  • New CVE Received by [email protected]

    Jul. 28, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'CasfID Servicios Tecnológicos', 'product': 'NFC Wristbands', 'versions': [{'status': 'affected', 'version': 'FM11RF08S variant', 'versionType': 'custom'}], 'defaultStatus': 'unaffected'}]
    Added Description 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.
    Added CVSS V4.0 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
    Added CWE CWE-326
    Added Reference https://www.incibe.es/en/incibe-cert/notices/aviso/insufficient-encryption-level-casfid-servicios-tecnologicos-nfc
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.