Vulnerability Monitor

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CVE-2021-33881

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.

Security Impact Summary

This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 4.2, but requires specific conditions to be met without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts integrity (unauthorized modifications), for affected systems. Impacting 16 products from nxp, from nxp, from nxp and 13 others, organizations running these solutions should prioritize assessment and patching.

Historical Context

Reported in 2021, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.

Published

2021-06-06T16:15:07.407

Last Modified

2024-11-21T06:09:42.567

Status

Modified

Source

[email protected]

Severity

CVSSv3.1: 4.2 (MEDIUM)

CVSSv2 Vector

AV:L/AC:M/Au:N/C:N/I:P/A:N

Access Vector: LOCAL
Access Complexity: MEDIUM
Authentication: NONE
Confidentiality Impact: NONE
Integrity Impact: PARTIAL
Availability Impact: NONE

Exploitability Score

3.4

Impact Score

2.9

Weaknesses

Type: Primary
CWE-863

Affected Vendors & Products

Type	Vendor	Product	Version/Range	Vulnerable?
Operating System	nxp	mifare_ultralight_ev1_firmware	-	Yes
Hardware	nxp	mifare_ultralight_ev1	-	No
Operating System	nxp	mifare_ultralight_c_firmware	-	Yes
Hardware	nxp	mifare_ultralight_c	-	No
Operating System	nxp	mifare_ultralight_nano_firmware	-	Yes
Hardware	nxp	mifare_ultralight_nano	-	No
Operating System	nxp	ntag_210_firmware	-	Yes
Hardware	nxp	ntag_210	-	No
Operating System	nxp	ntag_212_firmware	-	Yes
Hardware	nxp	ntag_212	-	No
Operating System	nxp	ntag_213_firmware	-	Yes
Hardware	nxp	ntag_213	-	No
Operating System	nxp	ntag_215_firmware	-	Yes
Hardware	nxp	ntag_215	-	No
Operating System	nxp	ntag_216_firmware	-	Yes
Hardware	nxp	ntag_216	-	No

References

https://blog.quarkslab.com/rfid-monotonic-counter-anti-tearing-defeated.html Mitigation, Third Party Advisory ([email protected])
https://www.nxp.com/docs/en/application-note/AN11340.pdf Vendor Advisory ([email protected])
https://www.nxp.com/docs/en/application-note/AN13089.pdf Vendor Advisory ([email protected])
https://www.sstic.org/2021/presentation/eeprom_it_will_all_end_in_tears/ Exploit, Third Party Advisory ([email protected])
https://blog.quarkslab.com/rfid-monotonic-counter-anti-tearing-defeated.html Mitigation, Third Party Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://www.nxp.com/docs/en/application-note/AN11340.pdf Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://www.nxp.com/docs/en/application-note/AN13089.pdf Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
https://www.sstic.org/2021/presentation/eeprom_it_will_all_end_in_tears/ Exploit, Third Party Advisory (af854a3a-2127-422b-91ae-364da2661108)

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For nxp's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.