CVE-2026-44362
Full vulnerability record from the local CVENow database.
Description
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 3.20.0 and prior to version 4.11.0, a vulnerability in OP-TEE’s subkey rollback protection allows the use of revoked or older subkey versions because the system fails to propagate versioning data during the Trusted Application (TA) loading process. In `core/crypto/signed_hdr.c`, the function `shdr_load_pub_key()` parses subkey headers but does not assign the `subkey_version` to the runtime `shdr_pub_key` structure. As a result, the `key->version` field remains at zero regardless of the version specified in the header. When `ree_fs_ta_open()` in `core/kernel/ree_fs_ta.c` calls `check_update_version()`, it passes this zeroed version to the rollback database. Because the database never receives a non-zero version to record, it never advances, effectively bypassing the rollback check and allowing TAs signed with downgraded subkey chains to load successfully. This impacts OP-TEE mainline configurations that utilize subkey-based signing chains for Trusted Application (TA) authentication. Version 4.11.0 contains a patch. No known workarounds are available.
View original CVE JSON
{
"id": "CVE-2026-44362",
"sourceIdentifier": "[email protected]",
"published": "2026-07-06T20:16:33.950",
"lastModified": "2026-10-25T20:10:00.147",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "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 3.20.0 and prior to version 4.11.0, a vulnerability in OP-TEE’s subkey rollback protection allows the use of revoked or older subkey versions because the system fails to propagate versioning data during the Trusted Application (TA) loading process. In `core/crypto/signed_hdr.c`, the function `shdr_load_pub_key()` parses subkey headers but does not assign the `subkey_version` to the runtime `shdr_pub_key` structure. As a result, the `key->version` field remains at zero regardless of the version specified in the header. When `ree_fs_ta_open()` in `core/kernel/ree_fs_ta.c` calls `check_update_version()`, it passes this zeroed version to the rollback database. Because the database never receives a non-zero version to record, it never advances, effectively bypassing the rollback check and allowing TAs signed with downgraded subkey chains to load successfully. This impacts OP-TEE mainline configurations that utilize subkey-based signing chains for Trusted Application (TA) authentication. Version 4.11.0 contains a patch. No known workarounds are available."
},
{
"lang": "es",
"value": "OP-TEE es un Entorno de Ejecución Confiable (TEE) diseñado como compañero de un kernel de Linux no seguro ejecutándose en núcleos Arm Cortex-A utilizando la tecnología TrustZone. A partir de la versión 3.20.0 y anterior a la versión 4.11.0, una vulnerabilidad en la protección de reversión de subclave de OP-TEE permite el uso de versiones de subclave revocadas o más antiguas porque el sistema no propaga los datos de versionado durante el proceso de carga de la Aplicación Confiable (TA). En ’core/crypto/signed_hdr.c’, la función ’shdr_load_pub_key()’ analiza los encabezados de subclave pero no asigna la ’subkey_version’ a la estructura ’shdr_pub_key’ en tiempo de ejecución. Como resultado, el campo ’key -> version’ permanece en cero independientemente de la versión especificada en el encabezado. Cuando ’ree_fs_ta_open()’ en ’core/kernel/ree_fs_ta.c’ llama a ’check_update_version()’, pasa esta versión puesta a cero a la base de datos de reversión. Debido a que la base de datos nunca recibe una versión no nula para registrar, nunca avanza, eludiendo efectivamente la verificación de reversión y permitiendo que las TA firmadas con cadenas de subclaves degradadas se carguen correctamente. Esto afecta a las configuraciones principales de OP-TEE que utilizan cadenas de firma basadas en subclaves para la autenticación de Aplicaciones Confiables (TA). La versión 4.11.0 contiene un parche. No se conocen soluciones alternativas disponibles."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "OP-TEE",
"product": "optee_os",
"versions": [
{
"version": ">= 3.20.0, < 4.11.0",
"status": "affected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "HIGH",
"availabilityImpact": "NONE"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-07-06T20:51:43.694755Z",
"id": "CVE-2026-44362",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-285"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:trustedfirmware:op-tee:*:*:*:*:*:*:*:*",
"versionStartIncluding": "3.20.0",
"versionEndIncluding": "4.10.0",
"matchCriteriaId": "D8F56A2E-B76A-4B45-AF68-2036283D85D6"
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"references": [
{
"url": "https://github.com/OP-TEE/optee_os/security/advisories/GHSA-fhcg-pp56-8v75",
"source": "[email protected]",
"tags": [
"Vendor Advisory"
]
}
]
}