The sensitive memory might be saved to disk, stored in a core dump, or remain uncleared if the product crashes, or if the programmer does not properly clear the memory before freeing it.
It could be argued that such problems are usually only exploitable by those with administrator privileges. However, swapping could cause the memory to be written to disk and leave it accessible to physical attack afterwards. Core dump files might have insecure permissions or be stored in archive files that are accessible to untrusted people. Or, uncleared sensitive memory might be inadvertently exposed to attackers due to another weakness.
Cleartext Storage of Sensitive Information in Memory
