2026-07-28 11:41CVE-2026-4648INCIBE
PUBLISHED5.2CWE-326

Insufficient Encryption Level in CasfID Servicios Tecnológicos NFC Wristbands

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.

Problem type

Affected products

CasfID Servicios Tecnológicos

NFC Wristbands

FM11RF08S variant - AFFECTED

References

GitHub Security Advisories

GHSA-4x9m-p82w-8mmp

Use of an insecure cryptographic algorithm in the cashless payment system using NFC wristbands...

https://github.com/advisories/GHSA-4x9m-p82w-8mmp

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.

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-4648
Click to expand
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