Attackers have been using Rich Text Format (RTF) files to carry exploits targeting vulnerabilities in Microsoft Office and other products. We documented one such incident in June 2009 (“details.rtf”). In a more recent example, the CVE-2012-0158 vulnerability was present in Active X controls within MSCOMCTL.OCX, which could be activated using Microsoft Office and other applications. McAfee described one such exploit, which appeared in the wild in April 2012:
“In the malicious RTF, a vulnerable OLE file is embedded with \object and \objocx tags. … Upon opening a crafted file with the vulnerable application, as in other document exploit files, we see an innocent file posing as bait, while in the background, the Trojan files are installed.”
How might you analyze a suspicious RTF file, perhaps delivered to you or your users as an email attachment? RTFScan, now available as part of Frank Boldewin’s OfficeMalScanner toolkit, can examine RTF files and assist in extracting embedded artifacts.