Dashboard / CVE-2026-40257

CVE-2026-40257

MEDIUM
MEDIUM Priority: 0.01 BB Relevance: 36/100
Published: 2026-07-06 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Interaction

CVSS Vector Breakdown

AV: Local
AC: Low
PR: Low
UI: None
S: Unchanged
C: None
I: None
A: High

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`.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
trustedfirmware op-tee 3.21.0 – 4.10.0

References & Advisories (1)

Bug Bounty Relevance

36 / 100
✓ Low complexity
✓ No user interaction

CVSS Score

5.5 / 10.0 v3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploitation Probability

0.15%
Raw Score 0.001530
Percentile 4.4%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00153
2026-10-28
0.00153

Intelligence Sources

nvd ref →

External Links