in February 2023, Kaspersky technologies detected a number of attempts to execute similar elevation-of-privilege exploits on Microsoft Windows servers belonging to small and medium-sized businesses in the Middle East, in North America, and previously in Asia regions. These exploits were very similar to already known Common Log File System (CLFS) driver exploits that we analyzed previously, but we decided to double check and it was worth it – one of the exploits turned out to be a zero-day, supporting different versions and builds of Windows, including Windows 11. The exploit was highly obfuscated with more than 80% of the its code being “junk” elegantly compiled into the binary, but we quickly fully reverse-engineered it and reported our findings to Microsoft. Microsoft assigned CVE-2023-28252 to the Common Log File System elevation-of-privilege vulnerability, and a patch was released on April 11, 2023, as part of April Patch Tuesday.
Microsoft addresses 97 CVEs, including one that was exploited in the wild as a zero day
Check Point Research recently discovered three vulnerabilities in the “Microsoft Message Queuing” service, commonly known as MSMQ. These vulnerabilities were disclosed to Microsoft and patched in the April Patch Tuesday update. The most severe of these, dubbed QueueJumper by CPR (CVE-2023-21554), is a critical vulnerability that could allow unauthorized attackers to remotely execute arbitrary code in the context of the Windows service process mqsvc.exe.
