CVE-2026-42546 op-tee vulnerability
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 3.3.0 and prior to version 4.11.0, a resource leak exists in OP-TEE’s shared memory cleanup logic because the function `cleanup_shm_refs()` in `core/tee/entry_std.c` fails to apply a required bitmask (`OPTEE_MSG_ATTR_TYPE_MASK`) to parameter attributes. When processing non-contiguous memory parameters from a normal-world caller, the system fails to match the attribute type in its internal switch statement and skips the necessary mobj_put() call. This results in a persistent reference leak of `mobj_reg_shm` objects, which remain on internal lists with dangling refcounts. This affects non-FF-A configurations that support non-contiguous, non-secure shared memory. Over time, these accumulated leaks progressively consume the secure-world heap, degrading the system's ability to service trusted application operations and eventually requiring a reboot to recover. Version 4.11.0 contains a patch. No known workarounds are available.
Quick answer
trustedfirmware op-tee should be reviewed and updated if it matches the affected versions. The recommended fix is to apply the vendor-supported patched version or the mitigation steps below, then retest the public website with Fixnx.
Who is affected
Affected versions
- Review vendor advisory for affected versions.
Fixed versions
- Apply the latest vendor-supported patched version.
How to fix it
OP-TEE is affected by CVE-2026-42546, a resource exhaustion risk. 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. The recommended remediation is to update to OP-TEE 4.11.0 or later. Until the update is complete, update trusted firmware and monitor shared memory cleanup behavior in affected OP-TEE deployments, review logs, and reduce exposure of the affected service, firmware path, or build workflow.
- Inventory every deployment, package, firmware image, appliance, device family, container, build runner, or service that uses OP-TEE.
- Confirm the installed version or firmware build and compare it with versions from 3.3.0 before 4.11.0 and the source advisory for CVE-2026-42546.
- Apply the vendor-supported fix: update to OP-TEE 4.11.0 or later.
- If the update cannot be applied immediately, update trusted firmware and monitor shared memory cleanup behavior in affected OP-TEE deployments; disable unnecessary public access, endpoints, uploads, build inputs, hardware features, or high-risk integrations until patched.
- Review application, device, kernel, firmware, build, package manager, container, authentication, and audit logs for activity related to CVE-2026-42546.
- Rotate sessions, API tokens, service credentials, signing keys, integration keys, and administrator passwords if logs or affected data indicate compromise, code execution, credential exposure, or unauthorized access.
- Clear caches, restart affected services, rebuild affected containers or firmware images when appropriate, and remove temporary files, generated artifacts, stored payloads, or unsafe configuration created during exploitation attempts.
Scan now. Google sign-in is only needed to unlock fix guidance.
Verify the fix
- Confirm OP-TEE now reports OP-TEE 4.11.0 or later or a later vendor-supported fixed release/build for the deployed branch or device family.
- Verify the affected workflow no longer allows the behavior described in CVE-2026-42546, using a safe regression test, vendor validation method, or firmware/package inventory check.
- Review logs after remediation for continued exploit attempts, denial-of-service symptoms, suspicious redirects, unauthorized requests, file access, memory corruption symptoms, or configuration changes.
- Rerun a Fixnx scan and any product-specific scanner, package audit, firmware inventory, device health check, or manual regression test relevant to the affected service.
- Document affected assets, fixed versions, mitigation decisions, validation evidence, and any cleanup, rebuild, or credential rotation performed.
Related categories
Trusted references
FAQ
What is affected by CVE-2026-42546?
trustedfirmware op-tee should be checked against the vendor advisory and trusted references linked on this page.
What should I fix first?
Start with internet-facing sites, admin panels, login flows, plugins, themes, modules, packages, and systems that process user-controlled input or sensitive data.
How do I confirm the fix worked?
Apply the patched version or mitigation, clear caches where relevant, retest the affected workflow, and run a new Fixnx scan to verify public website exposure signals.
How are Fixnx security risk categories chosen?
Fixnx keeps one canonical risk page and assigns only broad, relevant categories such as ecosystem, technology area, or vulnerability class.