The program accesses or uses a pointer that has not been initialized. If the pointer contains an uninitialized value, then the value might not point to a valid memory location. This could cause the program to read from or write to unexpected memory locations, leading to a denial of service. If the uninitialized pointer is used as a function call, then arbitrary functions could be invoked. If an attacker can influence the portion of uninitialized memory that is contained in the pointer, this weakness could be leveraged to execute code or perform other attacks. Depending on memory layout, associated memory management behaviors, and program operation, the attacker might be able to influence the contents of the uninitialized pointer, thus gaining more fine-grained control of the memory location to be accessed. 1000 699 Weakness ChildOf 119 699 Category ChildOf 465 1000 Weakness CanPrecede 125 1000 Weakness CanPrecede 787 There are close relationships between incorrect pointer dereferences and other weaknesses related to buffer operations. There may not be sufficient community agreement regarding these relationships. Further study is needed to determine when these relationships are chains, composites, perspective/layering, or other types of relationships. As of September 2010, most of the relationships are being captured as chains. Many weaknesses related to pointer dereferences fall under the general term of "memory corruption" or "memory safety." As of September 2010, there is no commonly-used terminology that covers the lower-level variants. Confidentiality Read memory If the uninitialized 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 uninitialized pointer references a memory location that is not accessible to the program, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur. Integrity Confidentiality Availability Execute unauthorized code or commands If the uninitialized pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible. CVE-2010-0211 chain: unchecked return value (CWE-252) leads to free of invalid, uninitialized pointer (CWE-824). CVE-2009-2768 Pointer in structure is not initialized, leading to NULL pointer dereference (CWE-476) and system crash. CVE-2009-1721 Free of an uninitialized pointer. CVE-2009-1415 Improper handling of invalid signatures leads to free of invalid pointer. CVE-2009-0846 Invalid encoding triggers free of uninitialized pointer. CVE-2009-0040 Crafted PNG image leads to free of uninitialized pointer. CVE-2008-2934 Crafted GIF image leads to free of uninitialized pointer. CVE-2007-4682 Access of uninitialized pointer might lead to code execution. CVE-2007-4639 Step-based manipulation: invocation of debugging function before the primary initialization function leads to access of an uninitialized pointer and code execution. CVE-2007-4000 Unchecked return values can lead to a write to an uninitialized pointer. CVE-2007-2442 zero-length input leads to free of uninitialized pointer. CVE-2007-1213 Crafted font leads to uninitialized function pointer. CVE-2006-6143 Uninitialized function pointer in freed memory is invoked CVE-2006-4175 LDAP server mishandles malformed BER queries, leading to free of uninitialized memory CVE-2006-0054 Firewall can crash with certain ICMP packets that trigger access of an uninitialized pointer. CVE-2003-1201 LDAP server does not initialize members of structs, which leads to free of uninitialized pointer if an LDAP request fails. Under-studied and probably under-reported as of September 2010. This weakness has been reported in high-visibility software, but applied vulnerability researchers have only been investigating it since approximately 2008, and there are only a few public reports. Few reports identify weaknesses at such a low level, which makes it more difficult to find and study real-world code examples. Mark Dowd John McDonald Justin Schuh The Art of Software Security Assessment Chapter 7, "Variable Initialization", Page 312. 1st Edition Addison Wesley 2006 MITRE 2010-09-22 CWE Content Team MITRE 2012-05-11 updated References