CVE-2026-40257
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk1th percentile - higher than 1% of all known CVEs
Summary
An off-by-one error in the ARM Crypto Extensions accelerated SHA-3 implementation in OP-TEE can cause a massive heap overflow, corrupting all TEE kernel memory after the hash state. Affected versions are from 3.21.0 to 4.11.0 with `CFG_CRYPTO_WITH_CE82=y`.
Risk Assessment
An attacker could exploit this overflow to completely corrupt TEE kernel memory, potentially leading to privilege escalation or arbitrary code execution within the trusted environment.
Recommendation
Upgrade OP-TEE to version 4.11.0 or later immediately. If upgrading is not possible, disable SHA-3 Crypto Extensions by setting `CFG_CRYPTO_WITH_CE82=n` as a workaround.
Original NVD description (English source)
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`.