Integer overflow in the CFDataReplaceBytes function in the CFData API in CoreFoundation in Apple Mac OS X before 10.5.3 allows context-dependent attackers to execute arbitrary code or cause a denial of service (crash) via an invalid length argument, which triggers a heap-based buffer overflow.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.