OP-TEE optee_os up to 4.10.x sp_mem_remove receivers use after free

Summaryinfo

A vulnerability has been found in OP-TEE optee_os up to 4.10.x and classified as critical. This affects the function sp_mem_remove. This manipulation of the argument receivers causes use after free. This vulnerability is handled as CVE-2026-40290. It is possible to launch the attack on the local host. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in OP-TEE optee_os up to 4.10.x. It has been declared as critical. Affected by this vulnerability is the function sp_mem_remove. The manipulation of the argument receivers with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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 3.16.0 and prior to 4.11.0, a user-after-free (UAF) race condition exists in the shared memory teardown logic of FF-A within OP-TEE SPMC/SP flows. This only applies when OP-TEE is configured as an SPMC for S-EL0 SPs, that is, with `CFG_SECURE_PARTITION=y`. The function `sp_mem_remove()`, responsible for freeing entries in `smem->receivers` and `smem->regions`, fails to acquire the global `sp_mem_lock` before performing the `free()` operations. Concurrently, other code paths, such as `sp_mem_get_receiver()`, iterate over these same lists without holding a lock, or, like `sp_mem_is_shared()`, iterate while holding the lock but are not serialized against the unprotected `free()` in `sp_mem_remove()`. This creates a cross-thread race where a thread iterating the list can acquire a pointer to an entry (e.g., `struct sp_mem_map_region` or `struct sp_mem_receiver`), and then another thread calls `sp_mem_remove()`, freeing the object. When the first thread resumes and dereferences the pointer, it results in a Use-After-Free vulnerability. Version 4.11.0 fixes the issue.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-40290 since 04/10/2026. The exploitation appears to be easy. An attack has to be approached locally. Technical details are known, but no exploit is available.

Upgrading to version 4.11.0 eliminates this vulnerability.

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Productinfo

Vendor

• OP-TEE

Name

• optee_os

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10

Website

• Product: https://github.com/OP-TEE/optee_os/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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