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 v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/OP-TEE/optee_os/security/advisories/GHSA-75x4-j8p9-55qv	Mitigation Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:o:trustedfirmware:op-tee:*:*:*:*:*:*:*:*

History

07 Jul 2026, 18:56

Type	Values Removed	Values Added
First Time		Trustedfirmware op-tee Trustedfirmware
CPE		cpe:2.3:o:trustedfirmware:op-tee::::::::
References	~~() https://github.com/OP-TEE/optee_os/security/advisories/GHSA-75x4-j8p9-55qv -~~	() https://github.com/OP-TEE/optee_os/security/advisories/GHSA-75x4-j8p9-55qv - Mitigation, Patch, Vendor Advisory

06 Jul 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-06 17:16

Updated : 2026-07-07 18:56

NVD link : CVE-2026-40257

Mitre link : CVE-2026-40257

CVE.ORG link : CVE-2026-40257

JSON object : View

Products Affected

trustedfirmware

op-tee

CWE

CWE-787

Out-of-bounds Write

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