CVE-2019-18614

On the Cypress CYW20735 evaluation board, any data that exceeds 384 bytes is copied and causes an overflow. This is because the maximum BLOC buffer size for sending and receiving data is set to 384 bytes, but everything else is still configured to the usual size of 1092 (which was used for everything in the previous CYW20719 and later CYW20819 evaluation board). To trigger the overflow, an attacker can either send packets over the air or as unprivileged local user. Over the air, the minimal PoC is sending "l2ping -s 600" to the target address prior to any pairing. Locally, the buffer overflow is immediately triggered by opening an ACL or SCO connection to a headset. This occurs because, in WICED Studio 6.2 and 6.4, BT_ACL_HOST_TO_DEVICE_DEFAULT_SIZE and BT_ACL_DEVICE_TO_HOST_DEFAULT_SIZE are set to 384.

CVSS v3.0 7.8 HIGH
CVSS v2.0 4.6 MEDIUM

7.8^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

4.6^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 3.9 / Impact : 6.4

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://github.com/seemoo-lab/frankenstein/blob/master/doc/CVE_2019_18614.md	Third Party Advisory

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Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:cypress:cyw20735_firmware:-:*:*:*:*:*:*:*

cpe:2.3:h:cypress:cyw20735:-:*:*:*:*:*:*:*

Information

Published : 2020-06-16 07:15

Updated : 2020-06-24 12:09

NVD link : CVE-2019-18614

Mitre link : CVE-2019-18614

JSON object : View

CWE

CWE-787

Out-of-bounds Write

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Products Affected

cypress

cyw20735
cyw20735_firmware

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