CasfID Servicios Tecnológicos NFC Wristbands FM11RF08S variant risky encryption

Summaryinfo

A vulnerability marked as problematic has been reported in CasfID Servicios Tecnológicos NFC Wristbands FM11RF08S variant. This issue affects some unknown processing. The manipulation leads to risky encryption. This vulnerability is traded as CVE-2026-4648. An attack has to be approached locally. There is no exploit available.

Detailsinfo

A vulnerability was found in CasfID Servicios Tecnológicos NFC Wristbands FM11RF08S variant. It has been rated as problematic. This issue affects an unknown code. The manipulation with an unknown input leads to a risky encryption vulnerability. Using CWE to declare the problem leads to CWE-327. The product uses a broken or risky cryptographic algorithm or protocol. Impacted is confidentiality. The summary by CVE is:

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.

The advisory is shared at incibe.es. The identification of this vulnerability is CVE-2026-4648 since 03/23/2026. The exploitation is known to be difficult. An attack has to be approached locally. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1600 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• CasfID Servicios Tecnológicos

Name

• NFC Wristbands

Version

• FM11RF08S variant

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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