CVE-2026-71967

OP-TEE OS through 4.10.0, fixed in commit 0aadfc2, contains a null pointer dereference vulnerability in the Widevine pseudo-TA open_session handler that allows Normal World clients to cause a denial of service when CFG_WIDEVINE_PTA is enabled. Attackers can open a session directly on the Widevine PTA to trigger an unconditional dereference of a NULL calling session pointer via is_user_ta_ctx(), faulting the TEE at S-EL1 and crashing the trusted execution environment.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/OP-TEE/optee_os/commit/0aadfc23407f50e770eb5ddd871fc208f5626833
https://github.com/OP-TEE/optee_os/pull/7899
https://www.vulncheck.com/advisories/op-tee-os-null-pointer-dereference-dos-via-widevine-pta-open-session

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-10 19:17

Updated : 2026-09-16 20:32

NVD link : CVE-2026-71967

Mitre link : CVE-2026-71967

CVE.ORG link : CVE-2026-71967

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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