A heap overflow, heap overrun, or heap smashing is a type of buffer overflow that occurs in the heap data area. Heap overflows are exploitable in a different manner to that of stack-based overflows. Memory on the heap is dynamically allocated at runtime and typically contains program data. Exploitation is performed by corrupting this data in specific ways to cause the application to overwrite internal structures such as linked list pointers. The canonical heap overflow technique overwrites dynamic memory allocation linkage (such as malloc metadata) and uses the resulting pointer exchange to overwrite a program function pointer.
For example, on older versions of Linux, two buffers allocated next to each other on the heap could result in the first buffer overwriting the second buffer's metadata. By setting the in-use bit to zero of the second buffer and setting the length to a small negative value which allows null bytes to be copied, when the program calls free() on the first buffer it will attempt to merge these two buffers into a single buffer. When this happens, the buffer that is assumed to be freed will be expected to hold two pointers FD and BK in the first 8 bytes of the formerly allocated buffer. BK gets written into FD and can be used to overwrite a pointer.
A heapoverflow, heap overrun, or heap smashing is a type of buffer overflow that occurs in the heap data area. Heapoverflows are exploitable in a different...
exploit a buffer overflow vulnerability vary by architecture, operating system, and memory region. For example, exploitation on the heap (used for dynamically...
Buffer overflow, a situation whereby the incoming data size exceeds that which can be accommodated by a buffer. Heapoverflow, a type of buffer overflow that...
algorithm Heapoverflow, a type of buffer overflow that occurs in the heap data area Sorites paradox, also known as the paradox of the heapHeap (surname)...
buffer overflow (or buffer overrun). Overfilling a buffer on the stack is more likely to derail program execution than overfilling a buffer on the heap because...
implementation-specific protections also exist against heap-based overflows. There are several implementations of buffer overflow protection, including those for the GNU...
works by bypassing a system security check using a memory exploit (heapoverflow) which occurs with USB devices that allows the execution of unsigned...
Man in the middle ARP poisoning VLAN hopping Smurf attack Buffer overflowHeapoverflow Format string attack SQL injection Phishing Cross-site scripting...
delete [] array; return res; } ==25372==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x61400000ffd4 at pc 0x0000004ddb59 bp 0x7fffea6005a0...
portions from a large pool of memory called the heap or free store. At any given time, some parts of the heap are in use, while some are "free" (unused) and...
behavior. Nearly 10% of application crashes on Windows systems are due to heap corruption. Modern programming languages like C and C++ have powerful features...
maximum. Also like heapsort, the priority queue is an implicit heap data structure (a heap-ordered implicit binary tree), which occupies a prefix of the...
such as accesses of uninitialized memory, accesses to freed memory, heapoverflow and underflow, and memory leaks. Its feature set is similar to that...
standard library, and as a result, has not been vulnerable to stack and heapoverflows, format string attacks, or temporary file race conditions. When it was...
commonly done using the heap segment. The allocator would usually expand and contract the heap to fulfill allocation requests. The heap method suffers from...
last public release in 2015. These vulnerabilities include stack and heapoverflows and denial-of-service attacks. Digital audio Audio file format Audio...
region, the code segment may be placed below the heap or stack in order to prevent heap and stack overflows from overwriting it. Computer programming portal...
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