Vulnerability Report

CVE-2026-33317

Title: OP-TEE OOB Read/Write in PKCS#11 TA

Memory Corruption

Proof Of Concept

PoC Available for CVE-2026-33317

CWE Category CWE-125

Published Date Apr 24, 2026

Modified Date Jun 05, 2026

Exploit Status Available

Score 8.7 CVSS v3.1

Exploit Probability (EPSS)

0.02%

Vulnerability Summary

CVE-2026-33317: 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. In versions 3.13.0 through 4.10.0, missing checks in `entry_get_attribute_value()` in `ta/pkcs11/src/object.c` can lead to out-of-bounds read from the PKCS#11 TA heap or a crash. When chained with the OOB read, the PKCS#11 TA function `PKCS11_CMD_GET_ATTRIBUTE_VALUE` or `entry_get_attribute_value()` can, with a bad template parameter, be tricked into reading at most 7 bytes beyond the end of the template buffer and writing beyond the end of the template buffer with the content of an attribute value of a PKCS#11 object. Commits e031c4e562023fd9f199e39fd2e85797e4cbdca9, 16926d5a46934c46e6656246b4fc18385a246900, and 149e8d7ecc4ef8bb00ab4a37fd2ccede6d79e1ca contain patches and are anticipated to be part of version 4.11.0.

Impacted Vendors

linaro 1

trustedfirmware 1

Reference Links

https://github.com/OP-TEE/optee_os/commit/149e8d7ecc4ef8bb00ab4a37fd2ccede6d79e1ca https://github.com/OP-TEE/optee_os/commit/16926d5a46934c46e6656246b4fc18385a246900 https://github.com/OP-TEE/optee_os/commit/e031c4e562023fd9f199e39fd2e85797e4cbdca9 https://github.com/OP-TEE/optee_os/security/advisories/GHSA-8cqw-mg7v-c9p9

CVSS v3.1

Source Entity [email protected]

Severity HIGH

8.7

Attack Vector

LOCAL

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

CHANGED

RAW VECTOR CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L

Associated Attack Patterns (CAPEC)

Total: Patterns