According to Symantec the first exploitation of the vulnerability was discovered on 2008-11-29.
Vulnerable component: Adobe Reader
CVSSv3 score: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
CWE-ID: CWE-119 - Improper Restriction of Operations within the Bounds of a Memory Buffer
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to boundary error in the custom heap management system in Adobe Reader and Acrobat. A remote attacker can create a specially crafted PDF file, trick the victim into opening it, trigger heap-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Note: this vulnerability is being actively exploited in the wild.