A recently disclosed severe 17-year-old vulnerability in Microsoft Office that lets hackers install malware on targeted computers without user interaction is now being exploited in the wild to distribute a backdoor malware.
First spotted by researchers at security firm Fortinet, the malware has been dubbed Cobalt because it uses a component from a powerful and legitimate penetration testing tool, called Cobalt Strike.
Cobalt Strike is a form of software developed for Red Team Operations and Adversary Simulations for accessing covert channels of a system.
The vulnerability (CVE-2017-11882) that Cobalt malware utilizes to deliver the backdoor is a memory-corruption issue that allows unauthenticated, remote attackers to execute malicious code on the targeted system when opened a malicious file and potentially take full control over it.
This vulnerability impacts all versions of Microsoft Office and Windows operating system, though Microsoft has already released a patch update to address the issue. You can read more details and impact of the vulnerability in our previous article.
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Since cybercriminals are quite quick in taking advantage of newly disclosed vulnerabilities, the threat actors started delivering Cobalt malware using the CVE-2017-11882 exploit via spam just a few days after its disclosure.
According to Fortinet researchers, the Cobalt malware is delivered through spam emails, which disguised as a notification from Visa regarding rule changes in Russia, with an attachment that includes a malicious RTF document, as shown.
To read the original article:
https://thehackernews.com/2017/11/cobalt-strike-malware.html