Microsoft’s February 2022 Patch Tuesday Addresses 48 CVEs (CVE-2022-21989)

CVE-2022-21989 is an EoP vulnerability in the Windows Kernel and the only zero-day vulnerability addressed this month. According to Microsoft’s Exploitability Index rating, this vulnerability is more likely to be exploited, however it has not been actively exploited at the time this blog was published. The advisory does note that an attacker needs to take additional actions prior to exploitation of this vulnerability, which is evident by the “High” rating for “Attack Complexity” in the CVSSv3 score of 7.8.

CVE-2022-22005 is a RCE vulnerability in Microsoft SharePoint Server with a CVSSv3 score of 8.8. Microsoft rates this as “exploitation more likely,” however at this time no public proof-of-concept appears to exist. In order to exploit this vulnerability, an attacker would need to be authenticated and have the ability to create pages in SharePoint.

CVE-2022-21999, CVE-2022-22718, CVE-2022-22717 and CVE-2022-21997 are EoP vulnerabilities in Windows Print Spooler. CVE-2022-21999 and CVE-2022-22718 received CVSSv3 scores of 7.8 and were rated Exploitation More Likely. CVE-2022-22717 (CVSSv3 7.0) and CVE-2022-21997 (CVSSv3 7.1) were rated Less Likely. Discovery of CVE-2022-21999 was credited to Xuefeng Li and Zhiniang Peng of Sangfor at the Tianfu Cup. These are the same researchers who disclosed CVE-2021-34527, kicking off the PrintNightmare saga in June 2021. CVE-2022-21997 was disclosed by Bo Wu and CVE-2022-22717 was credited to Thibault Van Geluwe de Berlaere with Mandiant. As researchers continue to focus their time on discovering flaws in Print Spooler, it is likely that attackers are as well, therefore organizations should apply these updates urgently.

CVE-2022-21996 is an EoP vulnerability in Microsoft’s Win32k, a core kernel-side driver used in Windows. This vulnerability received a CVSSv3 score of 7.8 and is more likely to be exploited according to Microsoft. This vulnerability is similar to another EoP flaw from January’s Patch Tuesday release, CVE-2022-21882. CVE-2022-21882 has been actively exploited in the wild by threat actors and the Cybersecurity and Infrastructure Security Agency has added the vulnerability to it’s Known Exploited Vulnerabilities Catalog, requiring federal agencies to remediate the vulnerability by February 18. Interestingly enough, CVE-2022-21882 is a patch bypass for another vulnerability, CVE-2021-1732 according to RyeLv, one of the researchers credited with reporting the vulnerability to Microsoft.

CVE-2022-22715 is an EoP vulnerability in the Named Pipe File System. It is rated as Exploitation More Likely. To exploit this flaw, an attacker would need to have established a presence on the vulnerable system in order to run a specially crafted application. Successful exploitation would allow an attacker to run processes with elevated privileges. The vulnerability is credited to researchers at Kunlun Lab, who participated in the Tianfu Cup, China’s biggest hacking competition.