CVE-2026-40257
Out-of-bounds Write: Is CVE-2026-40257 real, exploitable, or a false positive? Here's the community verdict.
signals
public sources
Moderate signals. Triage by your actual exposure and reachability.
baseline read
auto · not a community verdict
Low signal — verdict needed
Few public signals point to active risk. Whether a scanner hit here is a true or false positive depends on your version and config — community verdicts decide.
Based on CVSS · FIRST EPSS
Confirm or dispute →CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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`.
References
Published
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