InfoSecBulletin Cybersecurity for mankind
Outlook displays an alert when a user receives an email from an unfamiliar address. The alert message says “You don’t often get email from [email protected]. Learn why this is important”. Microsoft refers to this as the First Contact Safety Tip. It is one of the anti-phishing measures provided by Exchange Online Protection (EOP) and Microsoft Defender for organizations using Office 365.
You can change how the First Contact Safety Tip is displayed in an HTML email by using CSS style tags.
New G-Door Vul Allow Hackers Bypass Microsoft 365 Security With Google Docs
CVE-2024-53961
Adobe alerts of critical ColdFusion bug with PoC exploit available
Splunk targets Bangladeshi market: Investing in local talent
Critical PHP Zero-Day Vulnerability found in Craft CMS To Gain RCE
For US$2.6bn, Mastercard acquires threat intelligence firm Recorded Future
Eight New ICS Advisories released by CISA
Authority Denies
Hacker claim ransomware attack on Indonesia’s state bank BRI
London-based company “Builder.ai” reportedly exposed 1.2 TB data
(CVE-2024-12727, CVE-2024-12728, CVE-2024-12729)
Sophos resolved 3 critical vulnerabilities in Firewall
“Workshop on Cybersecurity Awareness and Needs Analysis” held at BBTA
To hide the First Contact Safety Tip in an HTML email, we can change the background and font colors to white. This will make the alert effectively invisible to the end user.
<head>
</head>
<head>
<style>
a {
display: none;
}
td div {
color: white;
font-size: 0px;
}
table tbody tr td {
background-color: white !important;
color: white !important;
}
</style>
</head>
…[SNIP]…
By using this HTML code in an e-mail, the alert does not show up in the email body anymore!
Note that the e-mail preview (highlighted in red) still begins with the Safety Tip.
Responsible Disclosure:
After developing a proof of concept, and preparing an advisory, we made Microsoft aware of these issues through the Microsoft Researcher Portal (MSRC). Microsoft chose to not address this behavior for now: (Click here to read the full report)
