According to Symantec the first exploitation of the vulnerability was discovered on 2009-03-19.
Trojan.Tarodrop.L
Vulnerability details
Advisory: SB2011061501 - Remote code execution in JustSystems Ichitaro
Vulnerable component: Ichitaro
CVE-ID: CVE-2011-1331
CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C
CWE-ID: CWE-122 - Heap-based Buffer Overflow
Description:
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The weakness exists due to heap-based buffer overflow when handling malformed files. A remote attacker can create a specially crafted file, trick the victim into opening it, trigger memory corruption and execute arbitrary code on the system with privileges of the current user.
Successful exploitation of the vulnerability results in arbitrary code execution on the vulnerable system.
Note: the vulnerability was being actively exploited.
External links:
http://jvn.jp/en/jp/JVN87239473/index.html
http://jvndb.jvn.jp/en/contents/2011/JVNDB-2011-000043.html
https://www.symantec.com/connect/blogs/targeted-attacks-2011-using-ichitaro-zero-day-vulnerability
http://www.justsystems.com/jp/info/js11001.html
https://www.symantec.com/security_response/writeup.jsp?docid=2011-061507-2634-99
https://www.symantec.com/security_response/writeup.jsp?docid=2011-061507-2634-99&tabid=3
https://co.norton.com/security_response/print_writeup.jsp?docid=2011-061507-2634-99
https://users.ece.cmu.edu/~tdumitra/public_documents/bilge12_zero_day.pdf