CVE-2026-40257
Severity CVSS v4.0:
Pending analysis
Type:
CWE-787
Out-of-bounds Write
Publication date:
06/07/2026
Last modified:
07/07/2026
Description
OP-TEE is a Trusted Execution Environment (TEE) designed as companion to a non-secure Linux kernel running on Arm; Cortex-A cores using the TrustZone technology. Starting in version 3.21.0 and prior to version 4.11.0, the ARM Crypto Extensions accelerated SHA-3 implementation has an off-by-one error that can cause a massive heap overflow that corrupts all TEE kernel memory following the hash state. This affects all platforms built with `CFG_CRYPTO_WITH_CE82=y` (ARMv8.2+ with SHA3 Crypto Extensions). Version 4.11.0 contains a patch. As a workaround, disable SHA3 Crypto Extensions with `CFG_CRYPTO_WITH_CE82=n`.
Impact
Base Score 3.x
5.50
Severity 3.x
MEDIUM
Vulnerable products and versions
| CPE | From | Up to |
|---|---|---|
| cpe:2.3:o:trustedfirmware:op-tee:*:*:*:*:*:*:*:* | 3.21.0 (including) | 4.10.0 (including) |
To consult the complete list of CPE names with products and versions, see this page



