Welcome to this week’s edition of the Threat Source newsletter. Our goal is to get accurate threat intelligence to our audience as quickly as possible, with all the context you need to ask the right questions of your own environment: How at risk are we from this threat? Are we prepared for it? And what can we do about it? What you don’t often see is all the... well, frankly, “mess” involved in producing it. All the dead ends we followed until we could confirm those ends were as dead as a…
Classification: Important, Solution: Official Fix, Exploit Maturity: Not Defined, CVSSv3.1: 5.9, CVEs: CVE-2026-20354, CVE-2026-20355, Summary: Multiple vulnerabilities in the Secure/Multipurpose Internet Mail Extensions (S/MIME) decryption functionality of Cisco Secure Email could allow an unauthenticated, remote attacker to recover plain text from encrypted email messages. These vulnerabilities are due to insufficient validation of message integrity. An attacker could exploit these…