On NXP MIFARE Ultralight and NTAG cards, an attacker can interrupt a write operation (aka…
Priority LOW 20CWE-863Published · Updated
Key facts
- Attack vector
- Physical
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-863.
Summary
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.
Why it matters now
EPSS 0.00411 35th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 16
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:nxp:mifare_ultralight_ev1_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NXP |
| cpe:2.3:h:nxp:mifare_ultralight_ev1:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NXP |
| cpe:2.3:o:nxp:mifare_ultralight_c_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NXP |
| cpe:2.3:h:nxp:mifare_ultralight_c:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NXP |
| cpe:2.3:o:nxp:mifare_ultralight_nano_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NXP |
| cpe:2.3:h:nxp:mifare_ultralight_nano:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NXP |
| cpe:2.3:o:nxp:ntag_210_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NXP |
| cpe:2.3:h:nxp:ntag_210:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NXP |
| cpe:2.3:o:nxp:ntag_212_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NXP |
| cpe:2.3:h:nxp:ntag_212:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NXP |
- cpe:2.3:o:nxp:mifare_ultralight_ev1_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NXP
- cpe:2.3:h:nxp:mifare_ultralight_ev1:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NXP
- cpe:2.3:o:nxp:mifare_ultralight_c_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NXP
- cpe:2.3:h:nxp:mifare_ultralight_c:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NXP
- cpe:2.3:o:nxp:mifare_ultralight_nano_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NXP
- cpe:2.3:h:nxp:mifare_ultralight_nano:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NXP
- cpe:2.3:o:nxp:ntag_210_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NXP
- cpe:2.3:h:nxp:ntag_210:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NXP
- cpe:2.3:o:nxp:ntag_212_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NXP
- cpe:2.3:h:nxp:ntag_212:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NXP
Show 6 more CPE
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:nxp:ntag_213_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NXP |
| cpe:2.3:h:nxp:ntag_213:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NXP |
| cpe:2.3:o:nxp:ntag_215_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NXP |
| cpe:2.3:h:nxp:ntag_215:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NXP |
| cpe:2.3:o:nxp:ntag_216_firmware:-:*:*:*:*:*:*:* | not specified by NVD | Vulnerable | NXP |
| cpe:2.3:h:nxp:ntag_216:-:*:*:*:*:*:*:* | not specified by NVD | Running on | NXP |
- cpe:2.3:o:nxp:ntag_213_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NXP
- cpe:2.3:h:nxp:ntag_213:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NXP
- cpe:2.3:o:nxp:ntag_215_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NXP
- cpe:2.3:h:nxp:ntag_215:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NXP
- cpe:2.3:o:nxp:ntag_216_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NXP
- cpe:2.3:h:nxp:ntag_216:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·NXP
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-33881
- 2026-10-03 Alias added: GHSA-ff8p-pfwc-wjf2
References
Sources
- CVE-2021-33881 · CVE Program
- CVE-2021-33881 · NVD
- FIRST EPSS
- GHSA-ff8p-pfwc-wjf2 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences