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CVE-2021-40327
Trusted Firmware-M (TF-M) 1.4.0, when Profile Small is used, has incorrect access control. NSPE can access a secure key (held by the…
Medium5.9EPSS 1.2%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
Trusted Firmware-M (TF-M) 1.4.0, when Profile Small is used, has incorrect access control. NSPE can access a secure key (held by the Crypto service) based solely on knowledge of its key ID. For example, there is no authorization check associated with the relationship between a caller and a key owner.
Timeline
ID reserved
By mitre
- 5 months later
· 5 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 1.2% · top 31% of all CVEs (7 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.
Weakness
Affected products
n/a
- affected n/a
References (3)
- https://developer.arm.com/support/arm-security-updates (opens in a new tab)x_refsource_MISCx_transferred
- https://git.trustedfirmware.org/TF-M/trusted-firmware-m.git/ (opens in a new tab)x_refsource_MISCx_transferred
- https://tf-m-user-guide.trustedfirmware.org/docs/security/security_advisories/profile_small_key_id_encoding_vulnerability.html (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-40327)Record last updated .