CVE-2026-40257 Details
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`.
A heap overflow vulnerability has been identified in OP-TEE versions 3.21.0 prior to 4.11.0. The issue arises in the ARM Crypto Extensions accelerated SHA-3 implementation, specifically in 'sha3_accel.c'. An off-by-one error in the 'sha3_process()' function allows a Trusted Application to overwrite approximately 4 GB of TEE kernel memory, leading to a guaranteed crash of the TEE kernel. This vulnerability affects all platforms built with 'CFG_CRYPTO_WITH_CE82=y', which includes ARMv8.2 and later with SHA3 Crypto Extensions. The non-accelerated SHA-3 implementation is not affected.
Users can upgrade to OP-TEE version 4.11.0 or later, or disable SHA3 Crypto Extensions by setting 'CFG_CRYPTO_WITH_CE82=n'.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Jul 6, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/OP-TEE/optee_os/security/advisories/GHSA-75x4-j8p9-55qv | [email protected] | MitigationPatchVendor Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-787 | Out-of-bounds Write | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| trustedfirmware op-tee | >= 3.21.0, <= 4.10.0 |
CPE
Remediation
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Change History
3 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 7, 2026 | Initial Analysis | [email protected] |
| Jul 6, 2026 | CVE Modified | CISA-ADP |
| Jul 6, 2026 | New CVE Received | [email protected] |