Threat Source Newsletter (April 15, 2021)
Summary: Cisco Talos' April 15, 2021 newsletter covers Microsoft's Patch Tuesday release of 108 vulnerabilities, including four critical Exchange Server remote code execution flaws tracked as CVE-2021-28480 through CVE-2021-28483, the highest scoring 9.8 out of 10. It also describes attackers using collaboration platforms such as Discord and Slack for malware delivery, component retrieval and command and control, and notes Talos researchers found multiple Azure Sphere vulnerabilities patched that month.
Key Takeaway: Four new critical Exchange Server flaws arrived months after Microsoft disclosed Exchange zero-days that attackers were already exploiting in the wild, and 20 of the 108 vulnerabilities in this release were rated critical. Attackers are also running campaigns over Discord and Slack because that legitimate infrastructure may not be blocked in many network environments.
Read the original at Cisco Talos ↗
- Topics
- Vulnerabilities & Patching
- Mentions
- CVE-2021-28480CVE-2021-28481CVE-2021-28482CVE-2021-28483
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