A 2-year-old vulnerability in Microsoft Outlook continues to cause headaches for companies, as attackers are able to use a specific feature of the program to execute code and persist on previously infected systems, according to an advisory published by cybersecurity services firm FireEye.
The attack, which uses the Microsoft Outlook Security Feature Bypass Vulnerability (CVE-2017-11774) patched in October 2017, abuses the Outlook Home Page feature that allows a customized view to be shown for any e-mail folder. When exploited, the vulnerability allows code to run whenever an Outlook client homepage is opened.
While the issue was patched, and the vast majority of companies have the update, attackers have been able to circumvent the fix to gain persistence on already-compromised systems, says Matthew McWhirt, senior manager at FireEye.
"We definitely continue to see the Home Page functionality being used by attackers, even though it was patched back in 2017, over two years ago," he says. "We are also seeing attackers attempting to disable protections that the patch provides by circumventing some controls by modifying the registry on endpoints."
The alert comes after the United States' military warned in July that Iranian cyber espionage groups were using the issue as part of their attacks on targets in the United States, Europe, and the Middle East. Two Iranian groups — APT33 and APT34 — have used the attack since June 2018, according to FireEye. attackers circumvent outlook homepage
