A joint report from the Cybersecurity and Infrastructure
Security Agency (CISA), the Federal Bureau of Investigation (FBI) and the
broader U.S. government offers information about the commonly known
vulnerabilities exploited by sophisticated foreign cyber actors.
Outdated software and hardware remain one of the most
significant security problems for companies and organizations, and it’s a main
route attackers looking for a way in will take. Not surprisingly, bad actors
usually look for vulnerabilities that were never patched, even though, patches
are usually available.
It’s true that attackers sometimes use zero-day
vulnerabilities, exploits that are unknown and unpatched, but that’s the
exception and not the rule.
“The public and private sectors could degrade some
foreign cyber threats to U.S. interests through an increased effort to patch
their systems and implement programs to keep system patching up to date,” says
“A concerted campaign to patch these vulnerabilities
would introduce friction into foreign adversaries’ operational tradecraft and
force them to develop or acquire exploits that are more costly and less widely
effective. A concerted patching campaign would also bolster network security by
focusing scarce defensive resources on the observed activities of foreign
The most exploited vulnerabilities between 2016 and 2019
are: CVE-2017-11882, CVE-2017-0199, CVE-2017-5638, CVE-2012-0158,
CVE-2019-0604, CVE-2017-0143, CVE-2018-4878, CVE-2017-8759, CVE-2015-1641, and
According to cybersecurity specialists in the U.S. government,
Microsoft’s Object Linking and Embedding (OLE) technology is often exploited,
followed in second place by widespread Web framework known as Apache Struts.
Foreign actors from China, Iran, North Korea, and Russia
are the most frequent users of vulnerabilities, looking for companies and
organizations that have yet to apply the patches for the vulnerabilities
Finally, the landscape in 2020 looks a little bit
different, with bad actors exploiting unpatched VPN vulnerabilities, for Citrix
VPN or Pulse Secure VPN. Also, the surge of people working from home determined
criminals to target organizations whose hasty deployed Microsoft O365 without
implementing the necessary security measures.
The advisory also lists the mitigations for the mentioned
vulnerabilities, which most of the time can be done just by installing the