¡¾·ì϶¹«¸æ¡¿OpenSSH ȨÏÞÌáÉý·ì϶ (CVE-2021-41617)

°ä²¼¹¦·ò 2021-09-27

0x00 ·ì϶¸ÅÊö

CVE     ID

CVE-2021-41617

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2021-09-26

Àà      ÐÍ

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6.2 - 8.7

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PoC/EXP


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0x01 ·ì϶ÏêÇé

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OpenSSH ÊÇ SSH £¨Secure SHell£© ºÍ̸µÄÃâ·Ñ¿ªÔ´ÊµÏÖ ¡£

2021Äê9ÔÂ26ÈÕ£¬OpenSSHÏîÄ¿°ä²¼ÁËOpenSSH 8.8°²È«¸üУ¬½¨¸´ÁËOpenSSH 6.2 µ½ 8.7°æ±¾ÖÐµÄ sshd(8)ÖеÄÒ»¸öȨÏÞÌáÉý·ì϶£¨CVE-2021-41617£© ¡£

µ±sshd(8) ÔÚÖ´ÐÐ AuthorizedKeysCommand »ò AuthorizedPrincipalsCommand ʱ£¬Î´ÄÜÕýÈ·µØ³õʼ»¯£¬ÆäÖÐAuthorizedKeysCommandUser »ò AuthorizedPrincipalsCommandUser Ö¸Áî±»ÉèÖÃΪÒÔ·ÇrootÓû§Éí·ÝÔËÐÐ ¡£Ïà·´£¬ÕâЩºÅÁ¼Ì³Ð sshd(8) Æô¶¯Ê±µÄ×éµÄȨÏÞ£¬Æ¾¾ÝϵͳÅäÖÃµÄ·ÖÆç£¬¼Ì³ÐµÄ×é¿ÉÄÜ»áÈø¨Öú·¨Ê½»ñ×ԵñíµÄȨÏÞ£¬µ¼ÖÂȨÏÞÌáÉý ¡£

ÔÚ sshd_config(5) ÖУ¬AuthorizedKeysCommand ºÍ AuthorizedPrincipalsCommand ¶¼Ã»Óб»Ä¬ÈÏÆôÓà ¡£

 

Ó°ÏìÁìÓò

OpenSSH °æ±¾6.2 - 8.7

 

0x02 ´ëÖý¨Òé

Ŀǰ´Ë·ì϶ÒѾ­½¨¸´£¬½¨ÒéÊÜÓ°ÏìµÄÓû§ÊµÊ±Éý¼¶¸üе½OpenSSH 8.8 ¡£

ÏÂÔØÁ´½Ó£º

http://www.openssh.com/releasenotes.html

 

0x03 ²Î¿¼Á´½Ó

https://www.openssh.com/security.html

https://www.openssh.com/txt/release-8.8

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-41617

 

0x04 ¸üа汾

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ÈÕÆÚ

Åú¸ÄÄÚÈÝ

V1.0

2021-09-27

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0x05 Îĵµ¸½Â¼

CNVD£ºwww.cnvd.org.cn

CNNVD£ºwww.cnnvd.org.cn

CVE£ºcve.mitre.org

CVSS£ºwww.first.org

NVD£ºnvd.nist.gov

 

0x06 ¹ØÓÚGA»Æ½ð¼×

¹Ø×¢ÒÔϹ«¼ÒºÅ£¬»ñÈ¡¸ü¶à×ÊѶ£º

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