CVE-2019-19648 - Out-of-bounds Read

Severity

78%

Complexity

18%

Confidentiality

98%

In the macho_parse_file functionality in macho/macho.c of YARA 3.11.0, command_size may be inconsistent with the real size. A specially crafted MachO file can cause an out-of-bounds memory access, resulting in Denial of Service (application crash) or potential code execution.

In the macho_parse_file functionality in macho/macho.c of YARA 3.11.0, command_size may be inconsistent with the real size. A specially crafted MachO file can cause an out-of-bounds memory access, resulting in Denial of Service (application crash) or potential code execution.

CVSS 3.1 Base Score 7.8. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

CVSS 2.0 Base Score 6.8. CVSS Attack Vector: network. CVSS Attack Complexity: medium. CVSS Vector: (AV:N/AC:M/Au:N/C:P/I:P/A:P).

Demo Examples

Out-of-bounds Read

CWE-125

In the following code, the method retrieves a value from an array at a specific array index location that is given as an input parameter to the method


               
}
return value;// check that the array index is less than the maximum// length of the array
value = array[index];// get the value at the specified index of the array
// if array index is invalid then output error message// and return value indicating error
value = -1;

However, this method only verifies that the given array index is less than the maximum length of the array but does not check for the minimum value (CWE-839). This will allow a negative value to be accepted as the input array index, which will result in a out of bounds read (CWE-125) and may allow access to sensitive memory. The input array index should be checked to verify that is within the maximum and minimum range required for the array (CWE-129). In this example the if statement should be modified to include a minimum range check, as shown below.


               
...// check that the array index is within the correct// range of values for the array

Overview

First reported 5 years ago

2019-12-09 01:15:00

Last updated 5 years ago

2019-12-17 18:55:00

Affected Software

VirusTotal YARA 3.11.0

3.11.0

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