Back to overview

CVE-2026-40257

MEDIUM
5.5
CVSS 3.1
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`.

Metadata

CVE ID
CVE-2026-40257
State
PUBLISHED
Assigner
GitHub_M
Reserved
2026-04-10 17:31 UTC
Published
2026-07-06 16:26 UTC
Last updated
2026-07-06 18:57 UTC
Primary CWE
CWE-787
CWE-787: Out-of-bounds Write
Vendor / Product
OP-TEE / optee_os
Sources
cve.org  ·  NVD

Severity & Metrics

5.5 MEDIUM CVSS 3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC — CISA Coordinator
Exploitation
none
Automatable
no
Tech. Impact
partial
Affected products (1)
VendorProductPlatformVersions
OP-TEE optee_os — >= 3.21.0, < 4.11.0
Weakness (CWE)
CWESourceDescription
CWE-787 cna CWE-787: Out-of-bounds Write
CVSS scores (1)
ScoreSeverityVersionSourceVector
5.5 MEDIUM 3.1 cna CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
References (1)
Back to overview