CVE-2017-8924 - Integer Underflow (Wrap or Wraparound)

Severity

21%

Complexity

39%

Confidentiality

48%

The edge_bulk_in_callback function in drivers/usb/serial/io_ti.c in the Linux kernel before 4.10.4 allows local users to obtain sensitive information (in the dmesg ringbuffer and syslog) from uninitialized kernel memory by using a crafted USB device (posing as an io_ti USB serial device) to trigger an integer underflow.

The edge_bulk_in_callback function in drivers/usb/serial/io_ti.c in the Linux kernel before 4.10.4 allows local users to obtain sensitive information (in the dmesg ringbuffer and syslog) from uninitialized kernel memory by using a crafted USB device (posing as an io_ti USB serial device) to trigger an integer underflow.

CVSS 3.0 Base Score 4.6. CVSS Attack Vector: physical. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.0/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

CVSS 2.0 Base Score 2.1. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (AV:L/AC:L/Au:N/C:P/I:N/A:N).

Demo Examples

Integer Underflow (Wrap or Wraparound)

CWE-191

The following example subtracts from a 32 bit signed integer.


               
}
return 0;

The example has an integer underflow. The value of i is already at the lowest negative value possible, so after subtracting 1, the new value of i is 2147483647.

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