Untrusted Pointer Dereference
|ID: 822||Date: (C)2012-05-14 (M)2012-11-08|
|Type: weakness||Status: INCOMPLETE|
|Abstraction Type: Base|
The program obtains a value from an untrusted source, converts
this value to a pointer, and dereferences the resulting pointer.
Extended DescriptionAn attacker can supply a pointer for memory locations that the program is
not expecting. If the pointer is dereferenced for a write operation, the
attack might allow modification of critical program state variables, cause a
crash, or execute code. If the dereferencing operation is for a read, then
the attack might allow reading of sensitive data, cause a crash, or set a
program variable to an unexpected value (since the value will be read from
an unexpected memory location).There are several variants of this weakness, including but not necessarily
limited to:The untrusted value is directly invoked as a function call.In OS kernels or drivers where there is a boundary between "userland"
and privileged memory spaces, an untrusted pointer might enter through
an API or system call (see CWE-781 for one such example).Inadvertently accepting the value from an untrusted control sphere
when it did not have to be accepted as input at all. This might occur
when the code was originally developed to be run by a single user in a
non-networked environment, and the code is then ported to or otherwise
exposed to a networked environment.
Related Attack Patterns
|Confidentiality ||Read memory ||If the untrusted pointer is used in a read operation, an attacker
might be able to read sensitive portions of memory. |
|Availability ||DoS: crash / exit /
restart ||If the untrusted pointer references a memory location that is not
accessible to the program, or points to a location that is "malformed"
or larger than expected by a read or write operation, the application
may terminate unexpectedly. |
|IntegrityConfidentialityAvailability ||Execute unauthorized code or
commandsModify memory ||If the untrusted pointer is used in a function call, or points to
unexpected data in a write operation, then code execution may be
|CWE-822 ChildOf CWE-876 ||Category ||CWE-868 || |
- CVE-2007-5655 : message-passing framework interprets values in packets as pointers, causing a crash.
- CVE-2010-2299 : labeled as a "type confusion" issue, also referred to as a "stale pointer." However, the bug ID says "contents are simply interpreted as a pointer... renderer ordinarily doesn't supply this pointer directly". The "handle" in the untrusted area is replaced in one function, but not another - thus also, effectively, exposure to wrong sphere (CWE-668).
- CVE-2009-1719 : Untrusted dereference using undocumented constructor.
- CVE-2009-1250 : An error code is incorrectly checked and interpreted as a pointer, leading to a crash.
- CVE-2009-0311 : An untrusted value is obtained from a packet and directly called as a function pointer, leading to code execution.
- CVE-2010-1818 : Undocumented attribute in multimedia software allows "unmarshaling" of an untrusted pointer.
- CVE-2010-3189 : ActiveX control for security software accepts a parameter that is assumed to be an initialized pointer.
- CVE-2010-1253 : Spreadsheet software treats certain record values that lead to "user-controlled pointer" (might be untrusted offset, not untrusted pointer).
For more examples, refer to CVE relations in the bottom box.
White Box Definitions None
Black Box Definitions None
|CERT C++ Secure Coding ||MEM10-CPP ||Define and use a pointer validation
function || |