Out-of-bounds Write Affecting op-tee/optee_os package, versions [3.21.0,]
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-UNMANAGED-OPTEEOPTEEOS-17824408
- published6 Jul 2026
- disclosed6 Jul 2026
- creditUnknown
Introduced: 6 Jul 2026
NewCVE-2026-40257 (opens in a new tab)How to fix?
A fix was pushed into the master branch but not yet published.
Overview
Affected versions of this package are vulnerable to Out-of-bounds Write in the SHA-3 accelerated finalize process due to an off-by-one error. An attacker can cause a massive heap overflow that corrupts all TEE kernel memory following the hash state by leveraging the ARM Crypto Extensions with SHA3 Crypto Extensions enabled. This is only exploitable if CFG_CRYPTO_WITH_CE82 is set to y (ARMv8.2+ with SHA3 Crypto Extensions).
Workaround
This vulnerability can be mitigated by disabling SHA3 Crypto Extensions with CFG_CRYPTO_WITH_CE82=n.