CVE-2026-71969

OP-TEE OS through 4.10.0, fixed in commit 7b8b494, contains a buffer underwrite vulnerability in the RSA NOPAD encrypt and decrypt operations within the mbedTLS software backend and SE050 hardware driver that allows a malicious Trusted Application to corrupt secure-world heap memory by supplying an input length exceeding the RSA modulus size. When src_len exceeds rsa_len, the subtraction expression wraps to a large unsigned value, causing a subsequent memcpy to write attacker-controlled data before the destination buffer in S-EL1 secure-world heap memory.

CVSS v3 6.7 MEDIUM

6.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 0.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://blog.secmate.dev/posts/optee-vulnerabilities-disclosure/
https://github.com/OP-TEE/optee_os/commit/7b8b494e0a324cefec8ed386b7de413b44f1aaf3
https://github.com/OP-TEE/optee_os/pull/7808
https://github.com/OP-TEE/optee_os/pull/7898
https://www.vulncheck.com/advisories/op-tee-os-buffer-underwrite-via-rsa-nopad-encrypt-decrypt-operations

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-10 19:17

Updated : 2026-08-17 19:16

NVD link : CVE-2026-71969

Mitre link : CVE-2026-71969

CVE.ORG link : CVE-2026-71969

JSON object : View

Products Affected

No product.

CWE

CWE-124

Buffer Underwrite ('Buffer Underflow')

CWE-787

Out-of-bounds Write

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