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0x01 ·ì϶ÏêÇé

ÕâЩ·ì϶ԴÓÚÒ»¸öÃûΪnetworkd-dispatcherµÄsystemd×é¼þ£¬¸Ã×é¼þÊÇÓÃÓÚ systemd-networkd ÏνÓ״̬¸ü¸ÄµÄµ÷¶È·¨Ê½ÊØ»¤¹ý³Ì¡£

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l  ·ûºÅÁ´½Ó¾ºÕù£º¾ç±¾·¢ÏÖºÍsubprocess.Popen¶¼×ñÑ­·ûºÅÁ´½Ó¡£

l  Time-of-check-time-of-use£¨TOCTOU£©¾ºÕùǰÌᣨCVE-2022-29800£©£º¾ç±¾±»·¢ÏÖºÍËüÃDZ»ÔËÐÐÖ®¼äÓÐÒ»°´¹¦·ò¡£Äܹ»ÀûÓô˷ì϶½«networkd-dispatcher ÒÔΪÊôÓÚroot µÄ¾ç±¾´úÌæÎª²»ÊôÓÚroot µÄ¾ç±¾¡£

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Ó°ÏìÁìÓò

networkd-dispatcher < 2.2.1-0

 

0x02 ´ëÖý¨Òé

ĿǰÒѾ­½¨¸´ÁËÕâЩ·ì϶£¬Äܹ»Éý¼¶µ½×îа汾networkd-dispatcher 2.2.1-0¡£

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https://gitlab.com/craftyguy/networkd-dispatcher

https://manpages.ubuntu.com/manpages/focal/man8/networkd-dispatcher.8.html


0x03 ²Î¿¼Á´½Ó

https://www.microsoft.com/security/blog/2022/04/26/microsoft-finds-new-elevation-of-privilege-linux-vulnerability-nimbuspwn/

https://www.bleepingcomputer.com/news/security/new-nimbuspwn-linux-vulnerability-gives-hackers-root-privileges/

https://thehackernews.com/2022/04/microsoft-discovers-new-privilege.html

 

0x04 ¸üа汾

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