CVE-2021-33881
4.2 · MEDIUMOverview
CVE-2021-33881 is a medium-severity vulnerability affecting nxp mifare_ultralight_ev1_firmware. It was published on June 6, 2021 and has a CVSS 3.1 base score of 4.2 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.2, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from nxp. Update mifare_ultralight_ev1_firmware to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
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References
Frequently Asked Questions
What is CVE-2021-33881?
CVE-2021-33881 is a medium-severity vulnerability affecting nxp mifare_ultralight_ev1_firmware. It was published on June 6, 2021 and has a CVSS 3.1 base score of 4.2 (MEDIUM).
How severe is CVE-2021-33881?
This vulnerability has a CVSS 3.1 base score of 4.2, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2021-33881?
Check the references section for vendor advisories and patches from nxp. Update mifare_ultralight_ev1_firmware to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-33881?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-33881 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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