An out-of-bounds read vulnerability was discovered in the Bosch BME690 SensorAPI (C-driver) in version v1.0.3 and prior, specifically within the field data parsing logic in read_all_field_data (bme69x.c). The driver prefetches heater configuration registers into a contiguous 30-byte stack buffer (set_val) mapping IDAC, RES_HEAT, and GAS_WAIT tables. When parsing sensor field data, the gas_index is extracted using a 4-bit mask (0..15) but lacks boundary verification against the valid range (0..9). An attacker or a compromised peripheral mimicking a sensor on the I2C/SPI bus could return a payload with a gas index value of 10 or higher. This causes the driver to perform an out-of-bounds array access (set_val[20 + gas_index]), reading up to 6 bytes past the stack buffer. The leaked out-of-bounds byte is then written into the public gas_wait field, which may lead to measurement corruption or leak adjacent stack memory when telemetered or logged.
| Métrique | Valeur | Interprétation |
|---|---|---|
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AV (Vecteur d'Attaque)
Attack Vector
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Physical (P)
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Exploit nécessite un accès physique à l'appareil |
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AC (Complexité d'Attaque)
Attack Complexity
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Low (L)
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Peu de conditions requises pour exploiter |
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PR (Privilèges Requis)
Privileges Required
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None (N)
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Aucune authentification requise |
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UI (Interaction Utilisateur)
User Interaction
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None (N)
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Aucune interaction utilisateur nécessaire |
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S (Périmètre)
Scope
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Unchanged (U)
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Impact reste dans le périmètre du composant compromis |
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C (Impact Confidentialité)
Confidentiality Impact
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Low (L)
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Divulgation limitée d'informations |
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I (Impact Intégrité)
Integrity Impact
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Low (L)
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Modification limitée des données possible |
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A (Impact Disponibilité)
Availability Impact
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Low (L)
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Interruption partielle du service possible |