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CVE-2021-41355

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2021-10-12

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2021Äê10ÔÂ12ÈÕ£¬Î¢Èí½¨¸´ÁË .NET Core ºÍ Visual Studio ÖеÄÒ»¸öÐÅϢй¶·ì϶£¨CVE-2021-41355£©£¬¸Ã·ì϶¿ÉÄܻᵼÖÂÆ¾Ö¤ÒÔÃ÷ÎÄ´ó¾Öй¶£¬ÆäCVSSÆÀ·ÖΪ5.7£¬Ó°ÏìÁË.NET 5.0¡¢Microsoft Visual Studio 2019 ºÍPowerShell 7.1¡£

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PowerShell ÊÇÒ»¸ö¿çƽ̨µÄ¹¤×÷×Ô¶¯»¯½â¾ö¹æ»®£¬ÓɺÅÁîÐÐ shell¡¢¾ç±¾Ëµ»°ºÍÅäÖÃÖÎÀí¿ò¼Ü×é³É¡£PowerShell Äܹ»ÔÚ Windows¡¢Linux ºÍ macOS ÉÏÔËÐС£Windows Defender ÀûÓ÷¨Ê½½ÚÔ죨WDAC£©Ö¼ÔÚ±£»¤WindowsÉ豸ÃâÊÜDZÔڵĶñÒâÈí¼þÈëÇÖ£¬È·±£Ö»ÓÐÊÜÐÅÀµµÄÀûÓ÷¨Ê½ºÍÇý¶¯·¨Ê½Äܹ»ÔËÐУ¬´Ó¶ø×èÖ¹¶ñÒâÈí¼þºÍ²»±ØÒªµÄÈí¼þÆô¶¯¡£

Ŀǰ£¬Redmond ÒѾ­°ä²¼ÁË PowerShell 7.0.8 ºÍ PowerShell 7.1.5£¬ÒÔ½¨¸´ PowerShell 7 ºÍ PowerShell 7.1 ·ÖÖ§Öеݲȫ·ì϶CVE-2020-0951ºÍCVE-2021-41355¡£ÓÉÓÚ¹¥»÷ÕßÄܹ»ÀûÓÃÕâЩ·ìÏ¶ÈÆ¹ýWDACÇ¿ÔìÖ´Ðв¢»ñµÃ¶Ô´¿Îı¾Í´´¦µÄ½Ó¼ûȨÏÞ£¬Î¢ÈíÒªÇóϵͳÖÎÀíԱΪPowerShell 7¸üв¹¶¡¡£

 

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Õâ2¸ö·ì϶ӰÏìÁËPowerShell 7µÄÒÔϰ汾£º

CVE-2021-41355£ºPowerShell 7.1

CVE-2020-0951£ºPowerShell 7.0 ¡¢PowerShell7.1

 

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ĿǰÕâЩ·ì϶ÒѾ­½¨¸´¡£Õë¶ÔPowerShell £¬½¨ÒéÊÜÓ°ÏìµÄÓû§ÊµÊ±Éý¼¶¸üе½PowerShell 7.0.8 »ò PowerShell 7.1.5¡£Òª¼ì²âPowerShell 7 °æ±¾ÊÇ·ñÊܵ½Ó°Ï죬ÇëÔÚPowershell´°¿ÚÖÐÊäÈëºÅÁ$PSVersionTable¡£

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https://github.com/PowerShell/PowerShell#get-powershell

 

0x03 ²Î¿¼Á´½Ó

https://github.com/PowerShell/Announcements/issues/27

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-41355

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-0951

https://www.bleepingcomputer.com/news/microsoft/microsoft-asks-admins-to-patch-powershell-to-fix-wdac-bypass/

 

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CNVD£ºwww.cnvd.org.cn

CNNVD£ºwww.cnnvd.org.cn

CVE£ºcve.mitre.org

CVSS£ºwww.first.org

NVD£ºnvd.nist.gov

 

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