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CVE-2021-43267

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2021-11-04

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2021Äê11ÔÂ4ÈÕ £¬SentinelLabs µÄÑо¿ÈËÔ±ÔÚ Linux KernelµÄ TIPC Ä £¿éÖз¢ÏÖÁËÒ»¸ö¶ÑÒç³ö©¶´£¨CVE-2021-43267£© £¬¸Ã©¶´µÄCVSSÆÀ·ÖΪ9.8¡£¹¥»÷Õß¿ÉÒÔÔ¶³Ì»òµ±µØÀûÓôË©¶´ÒÔÖ´ÐÐÈÎÒâ´úÂë £¬»ñÈ¡ÄÚºËȨÏÞ £¬´Ó¶ø¹¥»÷Õû¸öϵͳ¡£

TIPC£¨Í¸Ã÷½ø³Ì¼äͨÐÅ£©ÊÇÒ»¸öרÃÅΪ¼¯ÈºÄÚͨÐÅÉè¼ÆµÄЭÒé¡£Ëü¿ÉÒÔÅäÖÃΪͨ¹ý UDP »òÖ±½Óͨ¹ýÒÔÌ«Íø´«ÊäÏûÏ¢¡£ÏûϢͨ±¨ÊÇÓÐ˳Ðò±£Ö¤¡¢ÎÞ¶ªÊ§ºÍÁ÷Á¿¿ØÖƵÄ¡£ÑÓ³Ùʱ¼ä±ÈÈκÎÆäËûÒÑ֪ЭÒ鶼¶Ì £¬¶ø×î´óÍÌÍÂÁ¿¿ÉÓë TCP ÏàæÇÃÀ¡£

CVE-2021-43267ÓëÒ»ÖÖÃûΪ¡°MSG_CRYPTO¡±µÄеÄÓû§ÏûÏ¢ÀàÐÍÓйØ £¬¸ÃÏûÏ¢ÀàÐÍÓÚ 2020 Äê 9 ÔÂÍƳö £¬Ê¹¼¯ÈºÖеĶԵȽڵãÄܹ»·¢ËͼÓÃÜÃÜÔ¿£¨Ä¿Ç°ËƺõÖ»Ö§³ÖAES GCM£©¡£

ÔÚMSG_CRYPTOÏûÏ¢ÖÐ £¬±êÍ·¾ÞϸºÍÏûÏ¢¾Þϸ¶¼Æ¾¾Ýʵ¼ÊÊý¾Ý°ü¾Þϸ½øÐÐÑéÖ¤ £¬Òò´ËÕâЩֵ±£Ö¤ÔÚʵ¼ÊÊý¾Ý°üµÄ·¶Î§ÄÚ £¬µ«¶ÔÓÚMSG_CRYPTOÏûÏ¢µÄkeylen³ÉÔ±»òÃÜÔ¿Ëã·¨Ãû³Æ×Ô¼º£¨TIPC_AEAD_ALG_NAME£©µÄ¾Þϸ £¬²¢Ã»ÓÐÕë¶ÔÏûÏ¢¾ÞϸµÄÀàËƼì²é¡£ÕâÒâζ׏¥»÷Õß¿ÉÒÔ´´½¨Ò»¸öÌåÐͽÏСµÄÊý¾Ý°üÀ´·ÖÅä¶ÑÄÚ´æ £¬È»ºóʹÓÃkeylenÊôÐÔÖеÄÈÎÒâ¾ÞϸдÈë¸ÃλÖõĽçÏÞÖ®Í⣺

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´¥·¢Â©¶´µÄ MSG_CRYPTO ÏûϢʾÀý

¸Ã©¶´´æÔÚÓÚLinux KernelÖеÄnet/tipc/crypto.cÖÐ £¬Ô¶³Ì¹¥»÷Õß¿ÉÒÔͨ¹ýTIPC¹¦Ð§ÒÔÀûÓÃÓû§ÌṩµÄMSG_CRYPTOÏûÏ¢ÀàÐ;ÞϸÑéÖ¤²»×ãÀ´½øÐй¥»÷¡£´ËÍâ £¬TIPC Ä £¿éËæËùÓÐÖ÷Òª Linux ¿¯ÐаæÒ»ÆðÌṩ £¬µ«ÐèÒªÓû§¼ÓÔزÅÆøÆôÓøÃЭÒ飨·Çϵͳ×Ô¶¯¼ÓÔØ£©¡£

 

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5.10-rc1< Linux kernel °æ±¾< 5.15

 

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Ä¿Ç°´Ë©¶´ÒѾ­ÐÞ¸´ £¬½¨Ò齫Linux kernel¸üе½×îа汾5.15£¨ÒÑÓÚ2021Äê10ÔÂ31Ðû²¼£©¡£

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https://www.kernel.org/

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https://github.com/torvalds/linux/commit/fa40d9734a57bcbfa79a280189799f76c88f7bb0

 

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https://www.sentinelone.com/labs/tipc-remote-linux-kernel-heap-overflow-allows-arbitrary-code-execution/

https://thehackernews.com/2021/11/critical-rce-vulnerability-reported-in.html

https://www.zdnet.com/article/remote-code-execution-flaw-patched-in-linux-kernel-tipc-module/#ftag=RSSbaffb68

https://nvd.nist.gov/vuln/detail/CVE-2021-43267

 

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