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Vulnerability record · CVE-2026-40257 · published 6 July 2026

CVE-2026-40257: Trustedfirmware op-tee out-of-bounds write vulnerability

Trustedfirmware · Op Tee

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`.

5.5 CVSS 3.1 Medium EPSS 0.15% · top 96.2% CWE-787 · Out-of-bounds write
5.5CVSS 3.1 base score
0.15%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
1References
7 Jul 2026Last modified by NVD

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`.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

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

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2019-1010292Trustedfirmware op-tee out-of-bounds write vulnerabilityLinaro/OP-TEE OP-TEE Prior to version v3.4.0 is affected by: Boundary checks. The impact is: This could lead to corruption of any memory which the TA…EPSS 1.6%9.8CVE-2019-1010295Trustedfirmware op-tee improper input validation vulnerabilityLinaro/OP-TEE OP-TEE 3.3.0 and earlier is affected by: Buffer Overflow. The impact is: Memory corruption and disclosure of memory content. The compon…EPSS 1.6%9.8CVE-2019-1010293Trustedfirmware op-tee out-of-bounds write vulnerabilityLinaro/OP-TEE OP-TEE 3.3.0 and earlier is affected by: Boundary crossing. The impact is: Memory corruption of the TEE itself. The component is: optee…EPSS 1.6%9.8CVE-2019-1010298Trustedfirmware op-tee integer overflow vulnerabilityLinaro/OP-TEE OP-TEE 3.3.0 and earlier is affected by: Buffer Overflow. The impact is: Code execution in the context of TEE core (kernel). The compon…EPSS 3.9%9.8CVE-2019-1010296Trustedfirmware op-tee integer overflow vulnerabilityLinaro/OP-TEE OP-TEE 3.3.0 and earlier is affected by: Buffer Overflow. The impact is: Code execution in context of TEE core (kernel). The component …EPSS 2.8%9.8CVE-2019-1010297Trustedfirmware op-tee integer overflow vulnerabilityLinaro/OP-TEE OP-TEE 3.3.0 and earlier is affected by: Buffer Overflow. The impact is: Execution of code in TEE core (kernel) context. The component …EPSS 2.7%9.1CVE-2019-25052Trustedfirmware op-tee broken cryptographic algorithm vulnerabilityIn Linaro OP-TEE before 3.7.0, by using inconsistent or malformed data, it is possible to call update and final cryptographic functions directly, cau…EPSS 0.87%8.8CVE-2022-46152Trustedfirmware op-tee vulnerabilityOP-TEE Trusted OS is the secure side implementation of OP-TEE project, a Trusted Execution Environment. Versions prior to 3.19.0, contain an Improper…EPSS 0.49%

Source: NIST National Vulnerability Database (record CVE-2026-40257), CISA KEV, FIRST EPSS (scores of 2026-10-06). This page is refreshed as NVD updates the record.