Out-of-bounds Write Affecting optee-os package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-DEBIANUNSTABLE-OPTEEOS-17880044
- published7 Jul 2026
- disclosed6 Jul 2026
Introduced: 6 Jul 2026
CVE-2026-40257 (opens in a new tab)How to fix?
There is no fixed version for Debian:unstable optee-os.
NVD Description
Note: Versions mentioned in the description apply only to the upstream optee-os package and not the optee-os package as distributed by Debian.
See How to fix? for Debian:unstable relevant fixed versions and status.
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.