PatchTheCVECVE-2021-3011: An electromagnetic-wave side-channel issue was discovered on NXP SmartMX / P5x security microcontrollers and A
CVE-2021-3011 is a medium-severity flaw (CVSS 4.2) affecting k13, k21, k40. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
An electromagnetic-wave side-channel issue was discovered on NXP SmartMX / P5x security microcontrollers and A7x secure authentication microcontrollers, with CryptoLib through v2.9. It allows attackers to extract the ECDSA private key after extensive physical access (and consequently produce a clone). This was demonstrated on the Google Titan Security Key, based on an NXP A7005a chip. Other FIDO U2F security keys are also impacted (Yubico YubiKey
Why this priority
- Public exploit reference
No fix is published yet: follow the downgrade or mitigation steps.
Risk facts
| CVSS score | 4.2 (Medium) |
| Attack vector | Physical |
| Attack complexity | High |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.2% (top 90%) |
| CISA exploited list | No |
| Weakness | CWE-670 |
| Published | 2021-01-07 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2021-3011?
k13: mitigate or apply the listed mitigation; k21: mitigate or apply the listed mitigation; k40: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2021-3011 being exploited?
CVE-2021-3011 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2021-3011 affect?
CVE-2021-3011 affects k13, k21, k40. Severity is medium (CVSS 4.2). An electromagnetic-wave side-channel issue was discovered on NXP SmartMX / P5x security microcontrollers and A7x secure authentication microcontrollers, with CryptoLib through v2.9. It allows attackers to extract the ECDSA private key after
How urgent is CVE-2021-3011?
Priority 22/100. Public exploit reference