CVE-2026-40257

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`.

CVSS 3.1

5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS

0.2% chance of exploitation in the next 30 days; higher than 4% of CVEs (scores of 2026-10-25)

CWE

CWE-787

Published

2026-07-06

Modified

2026-10-25

Record from

the NVD, synced 2026-10-25

Affected

• trustedfirmware:op-tee

References

• https://github.com/OP-TEE/optee_os/security/advisories/GHSA-75x4-j8p9-55qv

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