Quote:Over half of exposed Exchange servers are still vulnerable to a severe bug that allows authenticated attackers to execute code remotely with system privileges – even eight months after Microsoft issued a fix.
The vulnerability in question (CVE-2020-0688) exists in the control panel of Exchange, Microsoft’s mail server and calendaring server. The flaw, which stems from the server failing to properly create unique keys at install time, was fixed as part of Microsoft’s February Patch Tuesday updates – and admins in March were warned that unpatched servers are being exploited in the wild by unnamed advanced persistent threat (APT) actors.
However, new telemetry found that out of 433,464 internet-facing Exchange servers observed, at least 61 percent of Exchange 2010, 2013, 2016 and 2019 servers are still vulnerable to the flaw.
“There are two important efforts that Exchange administrators and infosec teams need to undertake: verifying deployment of the update and checking for signs of compromise,” said Tom Sellers with Rapid7 in a Tuesday analysis.
Researchers warned in a March advisory that unpatched servers are being exploited in the wild by unnamed APT actors. Attacks first started in late February and targeted “numerous affected organizations,” researchers said. They observed attackers leverage the flaw to run system commands to conduct reconnaissance, deploy webshell backdoors and execute in-memory frameworks, post-exploitation.
Previously, in April, Rapid7 researchers found that more than 80 percent of servers were vulnerable; out of 433,464 internet-facing Exchange servers observed, at least 357,629 were open to the flaw (as of March 24). Researchers used Project Sonar, a scanning tool, to analyze internet-facing Exchange servers and sniff out which were vulnerable to the flaw.
Read more: https://threatpost.com/microsoft-exchang...aw/159669/