Microsoft Patch Tuesday for January 2021 fixes 83 flaws, including an actively exploited issue
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2021-1643 | HEVC Video Extensions Remote Code Execution Vulnerability HEVC Video Extensions Remote Code Execution Vulnerability NVD description · AI analysis pending | 7.8 | 4% |
| — | ||
| CVE-2021-1647 | Remote Code Execution Vulnerability in Microsoft Defender Antimalware Engine CVE-2021-1647 is a remote code execution flaw in Microsoft Defender's antimalware engine, categorized by CISA as a heap-based buffer overflow (CWE-122) arising from improper validation of crafted input values (CWE-1285). It is triggered when the Defender engine processes maliciously crafted content, for example a crafted file delivered via email or the web that Defender scans, causing the overflow during processing. Successful exploitation lets an attacker run arbitrary code on the target machine in the context of the Defender process, potentially leading to full system compromise. Any system running the affected Defender engine is exposed, including Windows 10 and Windows Server deployments where Defender is the default or widely deployed antivirus; the source data provides no fixed version numbers, only the vendor-issued update. The flaw is listed in CISA's Known Exploited Vulnerabilities catalog as of 2021-11-03, indicating exploitation has been observed in the wild, though no public PoC is known and ransomware use is listed as unknown. Do: Apply Microsoft's Defender antimalware engine/platform updates per vendor instructions and ensure Defender security intelligence and platform updates are enabled everywhere, including infrequently updated servers and endpoints. After updating, verify the Defender engine version on high-value hosts is current, prioritizing systems listed in CISA KEV remediation requirements. | 7.8 | 39% | KEV |
| mass≈1 billion+ Windows devices (Defender is the built-in AV on Windows 10 and ships broadly on Windows Server) | |
| CVE-2021-1667 | Remote Procedure Call Runtime Remote Code Execution Vulnerability Remote Procedure Call Runtime Remote Code Execution Vulnerability NVD description · AI analysis pending | 8.8 group max | 4% |
| — | ||
| CVE-2021-1677 | Azure Active Directory Pod Identity Spoofing Vulnerability Azure Active Directory Pod Identity Spoofing Vulnerability NVD description · AI analysis pending | 5.5 | 1% |
| — | ||
| CVE-2021-1705 | Microsoft Edge (HTML-based) Memory Corruption Vulnerability Microsoft Edge (HTML-based) Memory Corruption Vulnerability NVD description · AI analysis pending | 4.2 | 2% |
| — |
Full article531 words · extracted from securityaffairs.com · click to collapse
Microsoft Patch Tuesday security updates for January 2021 address 83 vulnerabilities, including a critical flaw actively exploited in the wild.
Microsoft Patch Tuesday security updates for January 2021 fix 83 security vulnerabilities in multiple products, including Microsoft Windows, Edge (EdgeHTML-based), ChakraCore, Office and Microsoft Office Services and Web Apps, Visual Studio, Microsoft Malware Protection Engine, .NET Core, ASP .NET, and Azure. 10 of these flaws are rated as Critical and 73 are rated as Important in severity. Seven of the addressed flaws were submitted through the ZDI program.
The IT giant has addressed a zero-day RCE flaw in Microsoft Defender, tracked as CVE-2021-1647, that resides in the Malware Protection Engine component (mpengine.dll).
The Microsoft Malware Protection Engine component provides the scanning, detection, and cleaning capabilities for Microsoft antimalware software.
Microsoft did not disclose details on the attacks in the wild that exploited this flaw.
The remaining critical remote code execution vulnerabilities addressed by the company are listed below:
| CVE | Title | Severity | Public | Exploited | Type |
| CVE-2021-1647 | Microsoft Defender Remote Code Execution Vulnerability | Critical | No | Yes | RCE |
| CVE-2021-1648 | Microsoft splwow64 Elevation of Privilege Vulnerability | Important | Yes | No | EoP |
| CVE-2021-1665 | GDI+ Remote Code Execution Vulnerability | Critical | No | No | RCE |
| CVE-2021-1643 | HEVC Video Extensions Remote Code Execution Vulnerability | Critical | No | No | RCE |
| CVE-2021-1668 | Microsoft DTV-DVD Video Decoder Remote Code Execution Vulnerability | Critical | No | No | RCE |
| CVE-2021-1705 | Microsoft Edge (HTML-based) Memory Corruption Vulnerability | Critical | No | No | RCE |
| CVE-2021-1658 | Remote Procedure Call Runtime Remote Code Execution Vulnerability | Critical | No | No | RCE |
| CVE-2021-1660 | Remote Procedure Call Runtime Remote Code Execution Vulnerability | Critical | No | No | RCE |
| CVE-2021-1666 | Remote Procedure Call Runtime Remote Code Execution Vulnerability | Critical | No | No | RCE |
| CVE-2021-1667 | Remote Procedure Call Runtime Remote Code Execution Vulnerability | Critical | No | No | RCE |
| CVE-2021-1673 | Remote Procedure Call Runtime Remote Code Execution Vulnerability | Critical | No | No | RCE |
The remaining vulnerabilities addressed by Microsoft Patch Tuesday for January are rated as “important” and are code execution, information disclosure, and denial-of-service issues.
Another interesting flaw addressed by Microsoft is a Microsoft splwow64 elevation of privilege vulnerability, tracked as CVE-2021-1648.
The flaw was discovered by the popular Google Project Zero expert Maddie Stone.
“While this issue is labeled as an elevation of privilege, it can also be exploited to disclose information. The type of information that could be disclosed if an attacker successfully exploited this vulnerability is uninitialized memory.” reads the security advisory published by Microsoft.
“This issue has been publicly disclosed by Google Project Zero (PZ2096) and the Zero Day Initiative (ZDI-CAN-11349 through 11351).”
As usually let me suggest reading the security update review published by the Zero Day Initiative that also highlights the importance of the following flaws addressed by Microsoft:
- CVE-2021-1677 – Azure Active Directory Pod Identity Spoofing Vulnerability
- CVE-2021-1674 – Windows Remote Desktop Protocol Core Security Feature Bypass Vulnerability
“In looking at the Important-rated bugs that could allow RCE, the SharePoint bug should not be ignored. It does require authentication, but it could allow an authenticated user to take complete control of the system.” states ZDI.
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(SecurityAffairs – hacking, Microsoft Patch Tuesday)
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Text extracted automatically; images, tables and formatting may be missing. Original: https://securityaffairs.com/113362/security/microsoft-patch-tuesday-for-january-2021-fixes-83-flaws-including-an-actively-exploited-issue.html