Use-After-Free in OP-TEE (CVE-2026-40290)
Summary
Vulnerability in OP-TEE (CVE-2026-40290). Successful exploitation can lead to full system takeover. Exploitable via sp_mem_lock.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-40290 has been found in OP-TEE.
Attackers can target a specific entry point like sp_mem_lock over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "OP-TEE CVE-2026-40290" on the vendor's site.
CVE-2026-40290 (OP-TEE) — CWE-416 / CVSS v3 7.8
Attack vector: local / no user interaction
Attack surface: sp_mem_lock
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Use-after-free (CWE-416) exists in OP-TEE. Attackers reach the vulnerable code path via sp_mem_lock.
Check the vendor advisory for the affected versions of OP-TEE. Attack surface: sp_mem_lock.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'OP-TEE' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'OP-TEE' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
OP-TEEを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-40290 optee-os
- Ubuntu UBUNTU-CVE-2026-40290 optee-os
References
- exploit github.com