cve/2021/CVE-2021-33881.md

### [CVE-2021-33881](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-33881)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen)

### Description

On NXP MIFARE Ultralight and NTAG cards, an attacker can interrupt a write operation (aka conduct a "tear off" attack) over RFID to bypass a Monotonic Counter protection mechanism. The impact depends on how the anti tear-off feature is used in specific applications such as public transportation, physical access control, etc.

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/ARPSyndicate/cvemon
- https://github.com/doegox/bibliography