User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the support for parsing Director movies. The .dir format is RIFF-based and is parsed mainly by the dirapi.dll module distributed with Shockwave. While parsing the Lnam chunk within a DIR file, the process attempts to extract a string into a fixed-length buffer located on the stack. The string is prefixed with a one byte size value. If the value is 0xFF the process blindly copies the following string until a NULL byte is found. This can be abused by an attacker to overflow the stack buffer and consequently execute arbitrary code under the context of the user running the browser.
