CVE-2021-44149
The OPTEE-OS CSU driver for NXP i.MX6UL SoC devices lacks security access configuration for wakeup-related registers, resulting in TrustZone bypass because the NonSecure World can perform arbitrary memory read/write operations on Secure World memory.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
An issue was discovered in Trusted Firmware OP-TEE Trusted OS through 3.15.0. The OPTEE-OS CSU driver for NXP i.MX6UL SoC devices lacks security access configuration for wakeup-related registers, resulting in TrustZone bypass because the NonSecure World can perform arbitrary memory read/write operations on Secure World memory. This involves a v cycle.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.34% probability · 27th percentile
- CISA KEV
- Not listed
- Affected
- trustedfirmware/op-tee
- Source
- cve@mitre.org
References
- https://github.com/OP-TEE/optee_os/tagsRelease Notes, Third Party Advisory
- https://github.com/f-secure-foundry/advisories/blob/master/Security_Advisory-Ref_FSC-HWSEC-VR2021-0002-OP-TEE_TrustZone_bypass_at_wakeup.txtThird Party Advisory
- https://github.com/OP-TEE/optee_os/tagsRelease Notes, Third Party Advisory
- https://github.com/f-secure-foundry/advisories/blob/master/Security_Advisory-Ref_FSC-HWSEC-VR2021-0002-OP-TEE_TrustZone_bypass_at_wakeup.txtThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.