CVE-2016-8688 - Out-of-bounds Read

Severity

43%

Complexity

86%

Confidentiality

48%

The mtree bidder in libarchive 3.2.1 does not keep track of line sizes when extending the read-ahead, which allows remote attackers to cause a denial of service (crash) via a crafted file, which triggers an invalid read in the (1) detect_form or (2) bid_entry function in libarchive/archive_read_support_format_mtree.c.

The mtree bidder in libarchive 3.2.1 does not keep track of line sizes when extending the read-ahead, which allows remote attackers to cause a denial of service (crash) via a crafted file, which triggers an invalid read in the (1) detect_form or (2) bid_entry function in libarchive/archive_read_support_format_mtree.c.

CVSS 3.0 Base Score 5.5. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H).

CVSS 2.0 Base Score 4.3. CVSS Attack Vector: network. CVSS Attack Complexity: medium. CVSS Vector: (AV:N/AC:M/Au:N/C:N/I:N/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 8 years ago

2017-02-15 19:59:00

Last updated 6 years ago

2018-11-30 11:29:00

Affected Software

libarchive 3.2.1

3.2.1

openSUSE Leap 42.2

42.2

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