Microsoft’s August 2022 Patch Tuesday Addresses 118 CVEs (CVE-2022-34713)

CVE-2022-34713, CVE-2022-35743 | Microsoft Windows Support Diagnostic Tool (MSDT) Remote Code Execution Vulnerabilities

CVE-2022-34713 and CVE-2022-35743 are RCE vulnerabilities in the Microsoft Windows Support Diagnostic Tool (MSDT) for troubleshooting. Both CVEs received a CVSS score of 7.8 and are rated important.

CVE-2022-34713 is credited to security researcher Imre Rad, who first disclosed the flaw in January 2020. At the time, Microsoft chose not to patch the flaw. However, following renewed interest in MSDT spurred by the discovery and exploitation of CVE-2022-30190 (aka Follina), Microsoft patched the flaw this month.

Security researcher j00sean resurfaced Rad’s “related” flaw in MSDT that was dubbed DogWalk, though Microsoft says CVE-2022-34713 is a “variant of” DogWalk that has been exploited in the wild.

A variety of attackers have incorporated Follina into their campaigns according to researchers at Proofpoint, Symantec and Cyberint, so we strongly advise organizations apply the available patches for these similar vulnerabilities as soon as possible.

CVE-2022-21980, CVE-2022-24516, CVE-2022-24477 | Microsoft Exchange Server Elevation of Privilege Vulnerabilities

CVE-2022-21980, CVE-2022-24516 andCVE-2022-24477 are EoP vulnerabilities in Microsoft Exchange Server. Microsoft has published a companion blog post for this Exchange Server update. All three received a CVSSv3 score of 8.0 and were rated “Exploitation More Likely” according to Microsoft’s Exploitability Index. Tianze Ding with Tencent Xuanwu Lab is credited with discovering these vulnerabilities. Yuhao Weng with Sangfor Zhiniang Peng with Sangfor also share credit for CVE-2022-21980.

All three vulnerabilities require authentication and user interaction to exploit — an attacker would need to entice a target to visit a specially crafted Exchange server, likely through phishing. Microsoft also notes that Extended Protection needs to be enabled to fully mitigate these vulnerabilities.

CVE-2022-35755, CVE-2022-35793 | Windows Print Spooler Elevation of Privilege Vulnerabilities

CVE-2022-35755 andCVE-2022-35793are EoP vulnerabilities in Windows Print Spooler Components that both received a CVSSv3 score of 7.3 and were rated “Exploitation More Likely.” These vulnerabilities were discovered by Xuefeng Li with Sangfor who has a long history of disclosing Print Spooler flaws, tracing back to the original PrintNightmare (CVE-2021-34527). CVE-2022-35755 can be exploited using a specially crafted “input file,” while exploitation of CVE-2022-35793 requires a user click on a specially crafted URL. Both would give the attacker SYSTEM privileges.

Both vulnerabilities can be mitigated by disabling the Print Spooler service, but CVE-2022-35793 can also be mitigated by disabling inbound remote printing via Group Policy.

CVE-2022-35804 | SMB Client and Server Remote Code Execution Vulnerability

CVE-2022-35804 is a RCE vulnerability affecting both the Server Message Block (SMB) client and server on Windows 11 systems using Microsoft SMB 3.1.1 (SMBv3). Microsoft rated this as “Exploitation More Likely” and assigned an 8.8 CVSSV3 score. This vulnerability is reminiscent of past SMB vulnerabilities such as the EternalBlue SMBv1 flaw patched in MS17-010 in March of 2017 that was exploited as part of the WannaCry incident in addition to the more recent CVE-2020-0796 “EternalDarkness” RCE flaw in SMB 3.1.1.

In March of 2022, Microsoft patched CVE-2022-24508, another similar RCE vulnerability impacting SMBv3. Fortunately that flaw has not seen exploitation in the wild, however any flaws impacting SMB always raise concerns of another WannaCry scenario. We strongly recommend patching this vulnerability as soon as possible. Microsoft does provide workaround guidance for organizations that are not able to immediately patch.

CVE-2022-34691 | Active Directory Domain Services Elevation of Privilege Vulnerability

CVE-2022-34691 is an EoP vulnerability affecting Active Directory Domain Services. With an 8.8 CVSSv3 score, this vulnerability could be exploited by an authenticated attacker to manipulate attributes of accounts and possibly acquire a certificate from Active Directory Certificate Services. This certificate would allow the attacker to elevate their privileges. The advisory notes that exploitation is only possible when Active Directory Certificate Services is running on the domain.

31 Elevation of Privilege Vulnerabilities in Azure Site Recovery

Azure Site Recovery, a suite of tools used for disaster recovery, had a significant number of CVE’s patched in this month's release, including 31 EoP vulnerabilities. CVSS scores range from 4.4 to 8.1 and all of the flaws were rated as Important and “Exploitation Less Likely.” A table of the vulnerabilities can be found below:

In our coverage of July’s Patch Tuesday release, we highlighted another EoP vulnerability discovered by Tenable Researcher Jimi Sebree alongside highlights of multiple additional vulnerabilities patched in the platform. With this month’s release, it’s clear that researchers continue to analyze cloud resources, helping to secure these services before attackers can capitalize on flaws in these highly valuable targets.