Microsoft Outlook for Mac Spoofing Vulnerability

What is the nature of the spoofing? An attacker could appear as a trusted user when they should not be. This could cause a user to mistakenly trust a signed email message as if it came from a legitimate user.

According to the CVSS metric, Integrity (I:L) is Low. What does that mean for this vulnerability? The attacker who successfully exploits the vulnerability could inject CSS (Cascading Style Sheets) into an email, which is rendered at the victim’s side when they view the email.