OP-TEE has FF-A type confusion in SPMC tmem path that causes S-EL1 kernel panic

published 2026-06-03 5 mo ago modified 2026-07-22 3 mo ago also EUVD-2026-34160

cvss: 4.4; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 4%
public exploits: 0; none known

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 4.3.0 and prior to version 4.11.0, a type confusion vulnerability exists in OP-TEE OS when processing an FFA_MEM_SHARE request from the normal world. This only applies when OP-TEE is configured as an SPMC for S-EL0 SPs, that is, with `CFG_CORE_SEL1_SPMC=y` and `CFG_SECURE_PARTITION=y`. Version 4.11.0 fixes the issue.

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-45702 updated 2026-06-28 cvss 4.4

optee-os: OP-TEE OS: Denial of Service via type confusion in FFA_MEM_SHARE request processing

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 5 mo ago (2026-06-04)

Exploit prediction

0.15% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/OP-TEE/optee_os/security/advisories/GHSA-86pj-8xgw-66p5 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	4.4	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

OP-TEE optee_os

Classification

Weakness

CWE-843 Access of Resource Using Incompatible Type

References

github.com /OP-TEE/optee_os/security/advisories/GHSA-86pj-8xgw-66p5
exploit, vendor-advisory

Sources

CVE List CVE-2026-45702
NVD CVE-2026-45702

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary