46%
39%
106%
In Android for MSM, Firefox OS for MSM, QRD Android, with all Android releases from CAF using the Linux kernel, in the function wma_ndp_end_indication_event_handler(), there is no input validation check on a event_info value coming from firmware, which can cause an integer overflow and then leads to potential heap overwrite.
In Android for MSM, Firefox OS for MSM, QRD Android, with all Android releases from CAF using the Linux kernel, in the function wma_ndp_end_indication_event_handler(), there is no input validation check on a event_info value coming from firmware, which can cause an integer overflow and then leads to potential heap overwrite.
CVSS 3.0 Base Score 7.8. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
CVSS 2.0 Base Score 4.6. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (AV:L/AC:L/Au:N/C:P/I:P/A:P).
The following image processing code allocates a table for images.
...
This code intends to allocate a table of size num_imgs, however as num_imgs grows large, the calculation determining the size of the list will eventually overflow (CWE-190). This will result in a very small list to be allocated instead. If the subsequent code operates on the list as if it were num_imgs long, it may result in many types of out-of-bounds problems (CWE-119).
The following code excerpt from OpenSSH 3.3 demonstrates a classic case of integer overflow:
}for (i = 0; i < nresp; i++) response[i] = packet_get_string(NULL);
If nresp has the value 1073741824 and sizeof(char*) has its typical value of 4, then the result of the operation nresp*sizeof(char*) overflows, and the argument to xmalloc() will be 0. Most malloc() implementations will happily allocate a 0-byte buffer, causing the subsequent loop iterations to overflow the heap buffer response.
Integer overflows can be complicated and difficult to detect. The following example is an attempt to show how an integer overflow may lead to undefined looping behavior:
}bytesRec += getFromInput(buf+bytesRec);
In the above case, it is entirely possible that bytesRec may overflow, continuously creating a lower number than MAXGET and also overwriting the first MAXGET-1 bytes of buf.
In this example the method determineFirstQuarterRevenue is used to determine the first quarter revenue for an accounting/business application. The method retrieves the monthly sales totals for the first three months of the year, calculates the first quarter sales totals from the monthly sales totals, calculates the first quarter revenue based on the first quarter sales, and finally saves the first quarter revenue results to the database.
}
return 0;// Variable for sales revenue for the quarter// Calculate quarterly total// Calculate the total revenue for the quarter
However, in this example the primitive type short int is used for both the monthly and the quarterly sales variables. In C the short int primitive type has a maximum value of 32768. This creates a potential integer overflow if the value for the three monthly sales adds up to more than the maximum value for the short int primitive type. An integer overflow can lead to data corruption, unexpected behavior, infinite loops and system crashes. To correct the situation the appropriate primitive type should be used, as in the example below, and/or provide some validation mechanism to ensure that the maximum value for the primitive type is not exceeded.
}
...// Calculate quarterly total// Calculate the total revenue for the quarter
Note that an integer overflow could also occur if the quarterSold variable has a primitive type long but the method calculateRevenueForQuarter has a parameter of type short.
This example demonstrates a shopping interaction in which the user is free to specify the quantity of items to be purchased and a total is calculated.
...
The user has no control over the price variable, however the code does not prevent a negative value from being specified for quantity. If an attacker were to provide a negative value, then the user would have their account credited instead of debited.
This example asks the user for a height and width of an m X n game board with a maximum dimension of 100 squares.
.../* board dimensions */die("No integer passed: Die evil hacker!\n");die("No integer passed: Die evil hacker!\n");die("Value too large: Die evil hacker!\n");
While this code checks to make sure the user cannot specify large, positive integers and consume too much memory, it does not check for negative values supplied by the user. As a result, an attacker can perform a resource consumption (CWE-400) attack against this program by specifying two, large negative values that will not overflow, resulting in a very large memory allocation (CWE-789) and possibly a system crash. Alternatively, an attacker can provide very large negative values which will cause an integer overflow (CWE-190) and unexpected behavior will follow depending on how the values are treated in the remainder of the program.
The following example shows a PHP application in which the programmer attempts to display a user's birthday and homepage.
echo "Birthday: $birthday<br>Homepage: <a href=$homepage>click here</a>"
The programmer intended for $birthday to be in a date format and $homepage to be a valid URL. However, since the values are derived from an HTTP request, if an attacker can trick a victim into clicking a crafted URL with <script> tags providing the values for birthday and / or homepage, then the script will run on the client's browser when the web server echoes the content. Notice that even if the programmer were to defend the $birthday variable by restricting input to integers and dashes, it would still be possible for an attacker to provide a string of the form:
2009-01-09--
If this data were used in a SQL statement, it would treat the remainder of the statement as a comment. The comment could disable other security-related logic in the statement. In this case, encoding combined with input validation would be a more useful protection mechanism.
Furthermore, an XSS (CWE-79) attack or SQL injection (CWE-89) are just a few of the potential consequences when input validation is not used. Depending on the context of the code, CRLF Injection (CWE-93), Argument Injection (CWE-88), or Command Injection (CWE-77) may also be possible.
This function attempts to extract a pair of numbers from a user-supplied string.
}
die("Did not specify integer value. Die evil hacker!\n");/* proceed assuming n and m are initialized correctly */
This code attempts to extract two integer values out of a formatted, user-supplied input. However, if an attacker were to provide an input of the form:
123:
then only the m variable will be initialized. Subsequent use of n may result in the use of an uninitialized variable (CWE-457).
The following example takes a user-supplied value to allocate an array of objects and then operates on the array.
}list[0] = new Widget();die("Negative value supplied for list size, die evil hacker!");
This example attempts to build a list from a user-specified value, and even checks to ensure a non-negative value is supplied. If, however, a 0 value is provided, the code will build an array of size 0 and then try to store a new Widget in the first location, causing an exception to be thrown.
This application has registered to handle a URL when sent an intent:
}......
}
}int length = URL.length();...
The application assumes the URL will always be included in the intent. When the URL is not present, the call to getStringExtra() will return null, thus causing a null pointer exception when length() is called.
ExploitPedia is constantly evolving. Sign up to receive a notification when we release additional functionality.
If you'd like to report a bug or have any suggestions for improvements then please do get in touch with us using this form. We will get back to you as soon as we can.