Attention Outlook users!
A recent case that is attracting attention is the #MonikerLink bug in Microsoft Outlook, a serious security vulnerability that allows attackers to execute malicious code on a user's computer simply by sending an email with a malicious link
What is the #MonikerLink bug?
The #MonikerLink bug exploits a specific way Outlook handles links and allows attackers to execute malware on other people's computers. This vulnerability, which has been given a critical severity rating of 9.8 on the CVSS scale, can be exploited by sending an email with a malicious link that is designed to trigger when the email is simply previewed in the preview pane. This means that the security risk is created without the recipient having to actively open the attachment or click on the link
How does the attack work?
Attackers send an email with a specially crafted "file://" hyperlink. When clicked, this link forces a connection to the attacker's server via the SMB protocol, sending sensitive NTLM credentials over the network. In addition, attackers can exploit Windows' Component Object Model (COM) to execute malicious code and gain further control over the victim's system
How can you protect yourself?
To protect themselves from such attacks, users should take a few important security measures:
1. be careful with links:
Never click on suspicious links or links from unknown senders. Be particularly careful with emails that are unexpected or from unknown sources.
2. update your software:
Always keep your IT systems up to date. Microsoft has already released a critical security update for Outlook in February 2024 (CVE-2024-21413). Users are urged to install this patch as soon as possible.
3. consider switching to cloud solutions:
Cloud-based solutions such as Office 365 or Google Workspace usually offer additional security measures and are continuously updated to ward off new threats.
What happens next?
The digital landscape is constantly changing, and security risks are evolving with it. The #MonikerLink bug in Microsoft Outlook is a serious example of how attackers can exploit known software to carry out malicious attacks. However, by following cybersecurity best practices, individuals and organisations can stay one step ahead and protect their digital assets.
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