CVE-2026-40290 — trustedfirmware / op-tee
Use After FreeOP-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.
| Software | From | Fixed in |
|---|---|---|
| trustedfirmware / op-tee | 3.16.0 | 4.10.0.x |
Deep Security Visibility Without the Complexity
SynScan provides clear, real-time security insights so you can monitor your attack surface, spot risks early, and act fast—without extra complexity.
- No setup fees
- 5-min deployment
- Cancel anytime
Frequently Asked Questions
A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.
Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.
Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.
SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.